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The Microsoft Year 2000 Resource Center Product Guide details specific Year 2000 information concerning Microsoft products. The information in the product guide is presented to assist IT professionals in planning their transition to the Year 2000. If you cannot find a specific product and it is not on the "Microsoft Products: Testing Yet to be Completed" list, you can assume it will NOT be tested for compliancy.
Microsoft will continually update the Year 2000 Product Guide with the most current Year 2000 test information. Visit the Year 2000 Product Guide for more details regarding the Microsoft Compliance Categories.

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Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Estonian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Estonian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Finnish)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Finnish OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (French)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: French OS: 32-Bit Win Release Date: 25 Mar 1999
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System Clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (German)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: German OS: 32-Bit Win Release Date: 25 Mar 1999
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System Clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Greek)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Greek OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Hebrew)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Hebrew OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Hindu)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Hindu OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Hungarian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Hungarian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Italian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Italian OS: 32-Bit Win Release Date: 25 Mar 1999
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System Clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Japanese)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Japanese OS: 32-Bit Win Release Date: 09 Jul 1999
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System Clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Korean)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Korean OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Latvian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Latvian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Lithuanian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Lithuanian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Norwegian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Norwegian OS: 32-Bit Win Release Date: 25 Mar 1999
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System Clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Pan-Chinese)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Pan-Chinese OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Polish)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Polish OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Portuguese (Brazil))

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Portuguese (Brazil) OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Portuguese)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Portuguese OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Romanian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Romanian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Russian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Russian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Serbian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Serbian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Slovak)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Slovak OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Slovenian)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Slovenian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Spanish)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Spanish OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Swedish)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Swedish OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Thai)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Thai OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 2000  9.0   (Turkish)

Product Summary
Product: Excel 2000 Version: 9.0 Category:Compliant
Language: Turkish OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows 95 or Windows 98, Windows NT 4 with Service Pack 3 or greater, or Windows NT 5
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Excel 2000 version 9.0 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 2000 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. When the system short date is a "yy" format, if a user types a 4-digit year (yyyy) date, it will, by default, display in a 2-digit year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.

The following optional registry setting can also be used to keep a "yyyy" format when a 4-digit date is entered: HKEY_CURRENT_USER\Software\ Microsoft\Office\9.0\Excel\Options::EnableFourDigitYearDisplay(DWORD)=1.

This setting only affects dates entered with 4-digit years: that is, entering "1/1/1925" will display "1/1/1925," but entering "1/1/25" will still display "1/1/25."

Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

  • Parsing on date entry. Excel 2000 uses a 100-year sliding window for the century assigned to a 2-digit year. By default, this time period is 1930-2029, but it can be changed in Windows 98 and Windows NT 5 by changing the setting on the Date tab in Regional Settings in Control Panel. For example, by changing the setting to 2019, the new sliding window would be 1920-2019. This interface controls the registry key: HKEY_CURRENT_USER\Control Panel\International\Calendars\TwoDigitYearMax\1(STRING).

    Because this is a system-wide setting, it will affect all programs that call the application programming interface (API); however, it will only affect older programs, such as Microsoft Access 97, which use OLE automation to determine dates. Also, because this change has broad impact on 2-digit date handling, including that in Microsoft Visual Basic (VB) and Microsoft Visual Basic for Applications (VBA), before making the change, users should consider all instances of where 2-digit years may be handled in Office or in their operating system. For more information, see the
    Office 2000 product guide.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 2000 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit year format, a solution is to replace the string dates in these formulas with true dates by using the DATE() function—that is, DATE(1999,12,31)—or to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling: See "Parsing on Date Entry" above.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel will parse the date using the rules in effect as described in "Parsing on Date Entry" above. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Entering =DATE(115,1,1) will result in January 1, 2015. To avoid problems, specify 4 digits for the year in the DATE() function.
  • Using a format such as "Dec 98" or "12/98" will not have the same interpretation at the year 2001. For example, because 98 is too large to be a day of the month, Excel interprets it is a year. However, Excel would interpret "Dec 01" as December 1 of the current year (See Knowledge Base article Q180952 for more information).
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • When dates must be transferred between programs—using methods other than cut, copy, and paste—ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as any of the following: February 1, 1925; January 2, 1925; February 1, 2025; January 2, 2025; January 25, 1902; or January 25, 2002. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users with a system short date format order other than the string date order will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date. For example, if a name is defined to refer to "2/1/99" by a user with "M/d/y" settings, the date will refer to February 1, 1999. When this same defined name and string are referred to by a user with "d/M/y settings, the date will resolve to January 2, 1999. Alternate interpretations can be avoided by replacing "2/1/99" in the string of the defined name with "=DATE(1999,2,1)".

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year—which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change the date formats in a workbook to formats that display the 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify that dates are being properly used. The following table can be used to guide testing of Excel 2000 within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as .txt, .dif, .csv, and .prn.
The default column width with default fonts may truncate characters with date formats that have eight digits and 2 separators. To avoid this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources
Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from earlier versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions
Date entry
Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to a different century. This may also help avoid issues with international users who have a system short- date format with an order other than M-d-y.

Additional testing instructions:

Excel 2000 has been designed for calculations well beyond the year 2000. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

Because Excel 2000 Beta 2 is a beta product, it has an expiration date; however, 2 time periods exist to allow users to verify that Excel is Year 2000 compliant. These periods are 12/15/1999 to 03/15/2000 and 12/15/2000 to 03/15/2001.

  • Test 1—Verify that Excel transitions smoothly into the year 2000:

    Warning!
    Before conducting this test, make sure you do not have any software that contains a license that expires by the year 2000. This is especially common with beta copies of software programs. (Read the paragraph above.) If a program determines that its license has expired, it is possible that the program will no longer boot, even after resetting the system clock. This can be particularly troublesome if you are running a beta operating system. Changing a system clock on a network can affect other computers that are connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:58 P.M., 12/31/1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 2 minutes, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2—Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year; however, in your testing, you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by four, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 2000 uses a number of Microsoft Office 2000 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find, and file I/O. For additional information that is appropriate for Excel 2000 please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 2000 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 4.0a    (English)

Product Summary
Product: Excel 4.0a Version: Category:Compliant#
Language: English OS: 16-Bit Win Release Date: 30 Oct 1992
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above, MS-DOS 5.0 or later
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

How the product handles dates:

Storage. By default, Microsoft Excel 4.0a stores dates as numeric values, with day #1 being 01-JAN-1900. Excel recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01-JAN-2000 is stored as value 36526, since it is the 36525 days after 01-JAN-1900. Excel can alternately use the 1904 date system, where day #1 is 02-JAN-1904.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date style. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 4 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as 01-JAN-1925. To avoid any possible confusion, users can display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article
Q181370 for more information.

Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base article
Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts two-digit year date formatting for your ODBC query, but assumes a date in the 1900s. To avoid this issue, you should use 4-digit years for queries based upon date data. The function DAYS360() will erroneously report an extra day when the date range spans a leap day.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date 01-JAN-1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Date entry using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting (See KB article
Q180952 for more information). Users with a "M-d-y" system short date style will encounter this issue more frequently than users with a "d-M-y" order.

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criteria by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a four digit year, but current versions of Microsoft Query also support windowing of two digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as 01-FEB-1925, 02-JAN-1925, 01-FEB-2025, 02-JAN-2025, 25-JAN-1902, 25-JAN-2002.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

File

Various File Formats

Avoid storing 2-year dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

 

Visual Data

 

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose much of an issue.

 

Visual Basic/Visual Basic for Applications

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 4.0a    (French)

Product Summary
Product: Excel 4.0a Version: Category:Compliant#
Language: French OS: 16-Bit Win Release Date: 30 Oct 1992
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above, MS-DOS 5.0 or later
Clock Dependencies: System clock
Last Updated: 09 Nov 1999
Product Details

How the product handles dates:

Storage. By default, Microsoft Excel 4.0a stores dates as numeric values, with day #1 being 01-JAN-1900. Excel recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01-JAN-2000 is stored as value 36526, since it is the 36525 days after 01-JAN-1900. Excel can alternately use the 1904 date system, where day #1 is 02-JAN-1904.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date style. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 4 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as 01-JAN-1925. To avoid any possible confusion, users can display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article
Q181370 for more information.

Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base article
Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts two-digit year date formatting for your ODBC query, but assumes a date in the 1900s. To avoid this issue, you should use 4-digit years for queries based upon date data. The function DAYS360() will erroneously report an extra day when the date range spans a leap day.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date 01-JAN-1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Date entry using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting (See KB article
Q180952 for more information). Users with a "M-d-y" system short date style will encounter this issue more frequently than users with a "d-M-y" order.

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criteria by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a four digit year, but current versions of Microsoft Query also support windowing of two digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as 01-FEB-1925, 02-JAN-1925, 01-FEB-2025, 02-JAN-2025, 25-JAN-1902, 25-JAN-2002.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

File

Various File Formats

Avoid storing 2-year dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

 

Visual Data

 

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose much of an issue.

 

Visual Basic/Visual Basic for Applications

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Arabic)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Arabic OS: 16-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 01 Dec 2078
Prerequisites: None
Product Dependencies: Arabic Windows 3.x, Arabic Windows 95/98 in both enabled and localized versions, Arabic Windows 95/98, Windows NT 4 Enabled
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details
  • Special Note for Arabic version of Excel: Arabic Excel 5 supports Hijri calendar.
  • Arabic Excel 5 has the ability to parse a date in Hijri date format. Day one of Hijri (01/01/01) is equivalent to July 16, 622 AD.
  • In most countries in the Middle East region, the popular date format is dd/mm/yy or dd/mm/yyyy. Arabic Excel 5 will try to format the date entered in a cell based on the Calendar chosen from the Tools/Options dialog, Arabic tab. Also Excel 5 will follow the Short Date format set from the Control Panel (ex: MM/dd/yy)
  • Arabic users can set the calendar to System, Gregorian or Hijri. When the calendar is set to System, it follows the Calendar in the Control Panel. In that case when the user types a date such as 12/30/98, and the short date format is MM/dd/yy then Excel parses the date in Gregorian unless the format of the date is proceeded by B2. When the calendar in Tools/Options… is set to Hijri, the dates will be parsed to Hijri without the B2 prefix, and likewise when set to Gregorian, dates will be parsed as Gregorian without the B1 prefix.
  • Arabic Excel 5 also allows the user to choose what month name to use in case of Arabic. This option is selected from Tools/Options as well. The options are System, Arabic, English, Transliterated English, and Transliterated French. If the case of System, Excel 5 will apply the above format to a date based on what country is selected in the Regional Settings and since these formats are Gregorian, there is no need for the B2 prefix.
  • Arabic Excel 5 also allows the user to turn on/off the Advanced Hijri date format independent of the Regional Settings in the Control Panel.
  • Arabic Excel 5 also has the ability to format a Gregorian date into a Hijri date by adding the prefix "B2" to the beginning of the format type, e.g. applying the format B2mm/dd/yy to the Gregorian date 12/31/98 in Arabic Excel results in the Hijri date 09/13/19, where 19 is the YY representation for year 1419. The "B2" string is applied in the Format Cells dialog, Number tab, Date category, or by using the NumberFormat property of the Range object using Visual Basic. To convert Hijri date into Gregorian, the "B2" prefix is omitted or the calendar option is changed to Gregorian in "Tools/Options…"
  • To convert a date from Gregorian to Hijri, the prefix "B2" is applied or the calendar option is changed to Hijri in Tools/Options…
  • Arabic Excel 5 does not parse a year into YYYY (4-digit year) even if the short date format in Control Panel was set to YYYY. Excel will start parsing a 4-digit year only when the user adds that format from Format Cells dialog.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/1/1. Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. Excel 5 adds 1900 or 2000 (based on 1920 cutoff) to 2-digit years, when a cell is formatted with the B2 prefix. This means that 2-digit years from 20-99 will refer to 1920-1999, while 2-digit years ranging from 00-19 refer to 2000-2019. If the calendar in Tools/Options is Hijri, Arabic Excel 5 adds the Hijri year 1400 to /2-digit years.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. Gregorian 12/31/2019 is equivalent to Hijri 05/05/1441, and Gregorian 01/01/1920 is equivalent to Hijri 04/10/1338. So from a Hijri date point of view, Arabic Excel 5 does not obey the "< 20 = 20XX" rule. This design is expected, as the year 2000 in Hijri does not occur for another 6 centuries.

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. The user copies the date, but the system settings are "M/d/yy", and the text that is copied is the text "1-1-15". When the user pastes "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base articles Q180159 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. The user cannot pass the DATE()function Hijri year, month and day. Even if the cell is formatted with B2 prefix, Arabic Excel 5 will calculate the Gregorian date based on the parameters passed to it and then will convert the date to Hijri. For example if the user formats a cell as B2mm/dd/yyyy and then types in it "=DATE(15,1,1)", the user will get 02/15/1333. Arabic Excel 5 looks at the parameters passed to DATE() and considers that as 01/01/1915 and then it converts to Hijri.
  • Recording date entry in a macro records the year in a YY (2-digit year) format, which can cause problems if the two-digit year is not meant to follow the 1920-2019 date window that is mentioned above.
  • To avoid confusion or miscalculations Arabic Excel 5 users should maintain a single type of date representation on the same sheet. If users decide to use Hijri, then they should use only Hijri.
  • Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 <http://support.microsoft.com/support/kb/articles/Q180/9/52.asp> for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products are difficult to predict. Interoperability testing with other Microsoft Office products can be conducted safely.

Testing

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are always stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid any ambiguity when reading or transferring dates. Not that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number, Date category, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Arabic Excel 5 transitions smoothly into the year 2000 when the Locale in Regional Settings is one of the Arabic countries: Warning! Before conducting this test, make sure you do not have software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Verify Arabic Excel 5 bumps the date that comes with the day 30 to the 1st day of the following month. With Short Date in the control panel set to MM/dd/yyyy and with the cell formatted to B2mm/dd/yyyy or with Hijri calendar on from Tools/Options… type in a cell "12/30/1419" and press Enter. Make sure that Excel bumps the date to 01/01/1420.
  • Set the system clock to 11:59 p.m. December 31, 1999 and then format the cell into B2dd/mm/yyyy. Start Arabic Excel 5. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. The resulting date shown should be 9/25/1420 Hijri, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". The resulting date should be February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Canadian French)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Canadian French OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity, we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Chinese - Simplified)

Product Summary
Product: Excel 5.0 Version: Category:Not Compliant
Language: Chinese - Simplified OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

Why is the product not compliant?

Depending on the date separators used, Excel 5.0 may recognize two-digit years as always falling in the 20th century. This can be avoided if users enter all 4-digits for the year when referring to a 21st century date. See below for more information.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/01/01. Excel 5.0 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (YY refers to a 2-digit year entry), then even when the user types a YYYY date, (4-digit year entry), it will by default display in a YY format. The date format is customizable. For customers requiring the highest level of assurance concerning the reliability of their date data, Microsoft recommends changing the system short date to a YYYY format.

Parsing on date entry.

  • If the system date separator matches the date separator used to enter a date with a two-digit year, it will parse to be a 1900 date. For instance if the system date separator is a dash, and the user enters a "yy-m-d" style date, then it will parse as a 1900 date. To avoid ambiguity, enter dates in a YYYY-M-D format.
  • If the system date separator does not match the date separator used to enter a date with a two digit year, it will parse such that a year less than 20 is 20XX, and equal to or greater than 20 is 19XX. For instance if the system date separator is a dash and the user enters a "yy/m/d" style date such as 25/1/1, it will parse to 01-JAN-1925. To avoid ambiguity, enter dates in a YYYY/M/D format.
  • On a default Chinese Simplified system, if a user enters a 21st century date in a "mm/yy/dd" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base (KB) article Q181370 http://support.microsoft.com/support/kb/articles/Q181/3/70.asp for more information.)

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.

(See Knowledge Base article Q164406 http://support.microsoft.com/support/kb/articles/Q164/4/06.asp for more information.)

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel 5.0 might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel 5.0, it will parse the date to January 1, 2015. This can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q182766 http://support.microsoft.com/support/kb/articles/Q182/7/66.asp for more information.)

  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q182766

http://support.microsoft.com/support/kb/articles/Q182/7/66.asp for more information.)

  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criteria by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Microsoft Excel 5.0 handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, in general they do have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2-digit format is used for the year. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Microsoft Excel 5.0 within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To resolve, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from:

text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates (for the year) will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit dates (for the year) to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language

Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this should not pose much of an issue.

Visual Basic/Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, VBA treats dates as serial values, exactly like Excel 5.0. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel 5.0.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 5.0. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 5. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel 5 recognizes the year 2000 as a leap year: Start Microsoft Excel 5.0. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 5 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel 5.0 treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 http://support.microsoft.com/support/kb/articles/Q181/3/70.aspfor more information.)

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Chinese - Traditional)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Chinese - Traditional OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: Operating system clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/01/01. Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (YY refers to a 2-digit year entry), then even when the user types a YYYY date (a 4-digit year entry), it will by default display in a YYYY format. The date format is customizable. For customers requiring the highest level of predictability concerning their date data, Microsoft recommends changing the system short date to a YYYY format
  • Parsing on date entry. If a user enters a date in a "yy-M-d" format, less than 20 is interpreted as 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "15-01-01" as January 1, 2015, but will recognize "25-01-01" as January 1, 1925. To avoid any possible confusion, however, users can display dates in a YYYY format so the century is clearly shown.
  • If a user enters a date in a "yy/mm/dd" format, it will be interpreted as a Republic of China era date. For instance, "1/2/3" will parse to 03 FEB 1912. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.
  • On a default Chinese Traditional system, if a user enters a 21st century date in a "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base (KB) article Q181370 for more information.)

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.

(See Knowledge Base article Q164406 for more information.)

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel 5 might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 1926 (R.O.C. era 15, January 1). This can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files.
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel 5 assumes "Dec 01" refers to December 1 of the current year. (See Knowledge Base article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criteria by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

  • Microsoft Excel 5 handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, in general they do have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, Jan. 2, 2025 or Feb. 1, 1936 (R.O.C. era 25, Feb. 1).
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2-digit format is used for the year. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To resolve, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from:

text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. In general, importing 2-digit dates will be parsed as R.O.C. era dates. They will parse as Gregorian dates with a 2019/1920 cutoff when the separator used for date entry is different from system setting (Ex: Date entry is 05-01-01 and date separator of system setting is "/" in the Control Panel – Regional Settings). This is different from later versions of Excel, so use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language

Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • In general, date entries will be parsed as R.O.C. era dates first. They will be parsed as Gregorian dates with a 2019/1920 cutoff when the separator used for date entry is different from system setting (Ex: Date entry is 05-01-01 and date separator of system setting is "/" in the Control Panel-Regional Settings).

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic/ Visual Basic for applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel 5.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 5. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 5. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel 5 recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 5 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel 5 treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Czech)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Czech OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System Clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Danish)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Danish OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Dutch)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Dutch OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (English)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: English OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Finnish)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Finnish OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (French)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: French OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (German)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: German OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Greek)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Greek OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Hebrew)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Hebrew OS: 16-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 01 Dec 2078
Prerequisites: None
Product Dependencies: Hebrew Windows 3.x, Hebrew Windows 95/98 in both enabled and localized versions, Hebrew Windows 95/98, Windows NT 4 Enabled
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

Special Note for Hebrew version of Excel:

  • Hebrew Excel 5 supports Hebrew Lunar calendar.
  • Hebrew Excel 5 has the ability to parse a date into a lunar Hebrew date. Day one of Gregorian (01/01/01 A.D.) is equivalent to 06-Tavis -3761 in Hebrew.
  • Hebrew Excel 5 will try to format the date entered in a cell based on the Calendar chosen from the Tools/Options dialog, Hebrew tab. Also Excel 5 will follow the Short Date format set from the Control Panel (ex: MM/dd/yy)
  • Hebrew Excel 5 allows Hebrew, English, and Transliterated English for month names.
  • Hebrew Excel 5 also has the ability to format a Gregorian date into a Hebrew date by adding the prefix "B2" to the beginning of the format type, e.g. applying the format B2mm/dd/yy to the Gregorian date 12/31/98 in Hebrew Excel results in the Hebrew date 12-Tavis-5759. The "B2" string is applied in the Format Cells dialog, Number tab, Date category, or by using the NumberFormat property of the Range object using Visual Basic.
  • To convert Hebrew dates into Gregorian, the "B2" prefix is omitted or the calendar option is changed to Gregorian in Tools/Options…
  • To convert a date from Gregorian to Hebrew, the prefix "B2" is applied or the calendar option is changed to Lunar in Tools/Options…
  • There is only one form of Hebrew calendar (Lunar Hebrew).
  • Hebrew Excel 5 does not parse a year into YYYY (4-digit year) even if the short date format in Control Panel was set to YYYY. Excel will start parsing a 4-digit year only when the user adds that format from Format Cells dialog.

 

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/1/1. Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates.
  • Excel 5 adds 1900 or 2000 (based on 1920 cutoff) to 2-digit years, when a cell is formatted with the B2 prefix. This means that 2-digit years from 20-99 will refer to 1920-1999, while 2-digit years ranging from 00-19 refer to 2000-2019. If the calendar in Tools/Options is Lunar, Hebrew Excel 5 adds the year 5700 to a date with 2-digit year.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. From a Hebrew Lunar point of view, the Year 2000 issue is not a critical problem because currently Lunar years are represented with 3 digits, with 5000 added implicitly.

 

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. The user copies the date, but the system settings are "M/d/yy", and the text that is copied is the text "1-1-15". When the user pastes "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. The user cannot pass the DATE()function Hebrew year, month and day.
  • Recording date entry in a macro records the year in a YY (2-digit year) format, which can cause problems if the two-digit year is not meant to follow the 1920-2019 date window that is mentioned above.
  • To avoid confusion or miscalculations Hebrew Excel 5 users should maintain a single type of date representation on the same sheet. If users decide to use Lunar, then they should use only Lunar dates.
  • Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 <http://support.microsoft.com/support/kb/articles/Q180/9/52.asp> for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products are difficult to predict. Interoperability testing with other Microsoft Office products can be conducted safely.

Testing

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number, Date category, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Hebrew Excel 5 transitions correctly into the year 2000 when the Locale in Regional Settings is set to Hebrew. Warning! Before conducting this test, make sure you do not have software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network so it is highly recommended isolating the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999 and then format the cell into B2dd/mm/yyyy. Start Hebrew Excel 5. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. The resulting date shown should be 22/04/5760 Hebrew Lunar Calendar and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". The resulting date should be February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

 

 

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Hungarian)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Hungarian OS: 16-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Italian)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Italian OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Japanese)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Japanese OS: 16-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/01/01. Excel 5.0 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. If the system short date is a YY format (YY refers to a 2-digit year entry), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 20 is interpreted as 20XX, and equal to or greater than 20 is 19XX. For example, Microsoft Excel 5 will recognize, 15-01-01" as January 1, 2015, but will recognize "25-01-01" as January 1, 1925. To avoid possible confusion, however, users can always display dates in a YYYY (4-digit year) format so the century is clearly shown.
  • If a user enters a date in a "yy/mm/dd" format, it will be interpreted as a Japanese era date. For instance, "1/2/3" will parse to 03 FEB 1989, or February 3, Heisei year 1. To avoid ambiguity, enter dates in a YYYY/MM/DD format so they can be clearly understood as Gregorian dates. Or enter dates with a prefix for the Japanese era, such as H, S, T, or M, so they can be understood as Japanese era dates.
  • On a default Japanese system, if a user enters a 21st century date in a "mm/yy/dd" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base (KB) article Q181370 for more information.)

Two-digit shortcut handling:

See discussion above.

(See Knowledge Base article Q164406 for more information.)

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel 5 might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1-1-15". When you paste "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q182766 for more information.)

  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel 5 assumes it is a year. However, Microsoft Excel 5 assumes "Dec 01" refers to December 1 of the current year. (See Knowledge Base article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

  • Serial date handling has the least potential for misinterpretation. Due to the ambiguous nature of text dates, in general they will have some potential for error. Consequently, you should use serial dates whenever possible when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Use 4-digit year formats for dates in Excel. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2-digit format is used for the year. Using defined names in this way can also create issues because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Microsoft Excel 5 within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To resolve, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from:

text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates (for the year) will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel so use 4-digit dates (for the year) to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language

Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic/ Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft provides the following Year 2000 testing guidelines for Microsoft Excel 5.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 5. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 5. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel 5 recognizes the year 2000 as a leap year: Start Microsoft Excel 5. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 5 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel 5 treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Korean)

Product Summary
Product: Excel 5.0 Version: Category:Not Compliant
Language: Korean OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: Operating system clock
Last Updated: 11 Nov 1999
Product Details

Why is the Product Not Compliant?

Excel 5.0 recognizes all two-digit years as the 20th century. This can be avoided if users enter all 4-digits for the year when referring to a 21st century date.

How the product handles dates:

  • Storage. Microsoft Excel 5.0 stores dates as numeric values, with day #1 being 1900/01/01. Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (YY refers to a 2-digit year entry), then even when the user types a YYYY date (4-digit year entry), it will by default display in a YY format. The date format is customizable. For customers requiring the highest level of assurance concerning the reliability of their date data, we recommend changing the system short date to a YYYY format.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" or "yy/mm/dd" format, it will parse to be a 1900 date, except for the year "00" which parses to 2000. To avoid ambiguity, enter dates in a YYYY-M-D or YYYY/M/D format.
  • On a default Korean system, if a user enters a date in an "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.

Leap Year. Microsoft Excel 5.0 treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base (KB) article Q181370 for more information.)

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes that 2-digit years are 20th century (19XX), except for the year "00" which parses to 2000.

(See Knowledge Base article Q164406 for more information.)

Common date usage errors:

  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel 5 assumes it is a year. However, Excel 5 assumes "Dec 01" refers to December 1 of the current year. (See Knowledge Base article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

  • Microsoft Excel 5 handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2-digit format is used for the year. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Microsoft Excel 5 within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from:

text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates (for the year) will be parsed such that two digit years are 20th century (19XX), except for the year "00" which parses to 2000. This is different from later versions of Excel, so use 4-digit dates (for the year) to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language

Functions

  • Functions referring to text dates will parse such that all two digit years are 20th century (19XX), except for the year "00" which parses to 2000. Date entry will parse such that all two-digit years are 20th century (19XX).

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic/ Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel 5.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 5. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 5. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel 5 recognizes the year 2000 as a leap year: Start Microsoft Excel 5. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 5 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel 5 treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Norwegian)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Norwegian OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Polish)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Polish OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Portuguese (Brazil))

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Portuguese (Brazil) OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

·         How the product handles dates:
Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900.  Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.


·         Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

·         Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

·         Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a  date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data.

Common date usage errors:

·         If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

·         The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

·         Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

·         Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

·         An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as “12/25”). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

·         Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

·         Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

·         Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

 

File

 

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

 

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

 

 

 

 

Additional Testing Instructions

Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.


·         Excel is designed to handle 2-digit year shortcuts well into the next century.  Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates.  Note that this change can affect column widths and print layout and it could require additional changes in your worksheets.  If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

·         Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

·         Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

·         Verify that Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Portuguese)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Portuguese OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Russian)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Russian OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Spanish)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Spanish OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Swedish)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Swedish OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Thai)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Thai OS: 16-Bit Win Release Date: 18 Apr 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Thai Windows 3.1 or above or Thai Win NT 4.0 or above
Clock Dependencies: System Clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Special notes for Thai version of Excel:

  • Thai Excel 5 supports the Buddhist calendar. Serial date 1 corresponds to January 1, 1900 in the Gregorian calendar and January 1, 2443 in the Buddhist calendar. The only difference between Buddhist and Gregorian dates is that Buddhist year number is 543 larger than the Gregorian.
  • Thai Excel 5 will parse the date entered in a cell according to the Short Date Style set in the Regional Settings of the Control Panel using the Gregorian calendar, even if the Calendar Type has been set to Buddhist.
  • A date in a cell can be expressed either as Buddhist or Gregorian by adjusting the cell format in the Format Cells dialog, on the Number tab, in the Custom category. Replacing yy with bb or yyyy with bbbb causes the date to be expressed with a 2- or 4-digit Buddhist year. Suppose the date May 15, 1998 (serial date 35930) is entered in a cell. Formatting the cell as d/m/yy will show 15/5/98, d/m/yyyy will show 15/5/1998, d/m/bb will show 15/5/41, and d/m/bbbb will show 15/5/2541.


Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

       
   

File

 

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

         

Data

 

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 5.0    (Turkish)

Product Summary
Product: Excel 5.0 Version: Category:Compliant#
Language: Turkish OS: 16-Bit Win Release Date: 31 Aug 1994
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 3.1 or above or Microsoft Windows NT 3.1 or above
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

How the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. . Excel 5 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (2-digit year), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)


Two-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, Microsoft recommends using 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB article Q182766 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)

Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.


Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

 

Component

 

File

Various File Formats

 

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

       

Data

Import from: text, Databases, External data sources Sort

 

Data imported from databases and other external sources is often imported as text. Importing 2-digit years will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit years to prevent confusion.

 

Basic Use

 

Functions Date Entry Natural Language Functions

 

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

         

Visual Data

 

Charts

 

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

         

VB/VBA

 

Transfer between VB/VBA and cells

 

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Arabic)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant#
Language: Arabic OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 01 Dec 2078
Prerequisites: None
Product Dependencies: Arabic Windows 95/98 in both enabled and localized versions
Clock Dependencies: System clock
Last Updated: 11 Nov 1999
Product Details

What are the acceptable deviations?
MS Query accepts 2-digit year date formatting for the user’s ODBC query, but assumes a twentieth century date. To avoid this issue, users should use 4- digit years for queries based upon date data.

Special Notes for Arabic version of Excel:

  • Arabic Excel 95 supports Hijri calendar
  • Arabic Excel 95 has the ability to parse a date in Hijri date format. Day one of Hijri (01/01/01) is equivalent to July 16, 622 AD.
  • In most countries in the Middle East region, the popular date format is dd/mm/yy or dd/mm/yyyy. Arabic Excel 95 will try to format the date entered in a cell based on what the Short Date Style has been set to in the Control Panel and in Gregorian calendar, even if the calendar in Control Panel has been set to Hijri.
  • Arabic Excel 95 also has the ability to format a Gregorian date into a Hijri date by appending the string "B2" to the beginning of the format type, e.g. applying the format B2mm/dd/yy to the Gregorian date 12/31/98 in Arabic Excel results in the Hijri date 09/13/19, where 19 is the YY representation for year 1419. The "B2" string is applied in the Format Cells dialog, Number tab/Custom or using the NumberFormat property of the Range object using Visual Basic for Applications.
  • To convert back a Hijri date back into Gregorian, the "B2" prefix is omitted.
  • Some Arabic countries in the Middle East use one of the following calendar types besides Hijri: Arabic Gregorian, Arabic Transliterated Gregorian, French Gregorian, and French Transliterated Gregorian. The date formats mentioned above are Gregorian and the only difference is the name of the month would be in Arabic, French, Arabic Transliterated or French Transliterated. Arabic Excel 95will apply the above format to a date based on what country is selected in the Regional Settings and since these formats are Gregorian, there is no need for the B2 prefix.
  • Hijri dates come with 29 or 30 days. When the user enters a date with the format B2 and with day 30, but that particular Hijri month happened to have 29 days only, Arabic Excel 95 will bump the date to the 1st day of the following month.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/1/1. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. If the system short date is a YYYY (4-digit year) format, when the user types a YY date (a 2-digit year entry), it will by default display in a YYYY format. Excel 95 adds 1900 or 2000 (based on 1920 cutoff) to 2-digit years. What this means is that 2-digit years that fall in the 00-19 range will be recognized as 2000-2019, while those 2-digit years that fall in the 20-99 range will be recognized as 1920-1999. When a cell is formatted with the B2 prefix, Arabic Excel 95 adds the Hijri year 1400 to 2-digit years.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. Gregorian 12/31/2019 is equivalent to Hijri 05/05/1441, and Gregorian 01/01/1920 is equivalent to 04/10/1338. So from a Hijri date point of view, Arabic Excel 95 does not obey the "< 20 = 20XX" rule and it should not, since the Hijiri calendar is about 6 centuries away from year 2000 Hijri.

 

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, a user has the date January 1, 1915. The user copies the date, but the system settings are "M/d/yy", and the text that is copied is "1-1-15". When the user pastes "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if the users were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. The user cannot pass the DATE()function Hijri year, month and day.
  • Recording date entry in a macro records the year in a YY (2-digit year) format, which can cause problems if the 2-digit year is not meant to follow the 1920-2019 date cutoff window that is mentioned above.
  • Since Visual Basic for Applications macro recorder uses English settings only and not Regional Settings and since Arabic Excel parses Hijri dates based on custom format and not based on the system calendar, it is not possible to have the recorder record a Hijri date entry.
  • Due to the ambiguous nature of text dates, use serial dates whenever possible and take great care when transferring text dates.
  • Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 <http://support.microsoft.com/support/kb/articles/Q180/9/52.asp> for more information.)"
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Recommendations:

    • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
    • To avoid confusion or miscalculations, Arabic Excel 95 users should maintain a single type of date representation on the same sheet. If a user decides to use Hijri, then they should use only Hijri.
    • Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y may experience miscalculations. It is highly recommended to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

 

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products are difficult to predict. Interoperability testing with other Microsoft Office products can be conducted safely.

Testing

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If the user decides not to set the system short date format to include a 4-digit year, the user can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Arabic Excel 95 transitions smoothly into the year 2000 when the Locale in Regional Settings is one of the Arabic countries: Warning! Before conducting this test, make sure you do not have software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Verify Arabic Excel 95 changes the date that comes with the day 30 to the 1st day of the following month. With Short Date in the control panel set to MM/dd/yyyy and with the cell formatted to B2mm/dd/yyyy, type in a cell "12/30/1419" and press Enter. Make sure that Excel changes the date to 01/01/1420.
  • Set the system clock to 11:59 p.m. December 31, 1999 and then format the cell into B2dd/mm/yyyy. Start Arabic Excel 95. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the date shown will be 9/25/1420 Hijri, and nothing unusual has happened to Microsoft Excel. Remember to reset the system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.

 

 

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Canadian French)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Canadian French OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites:

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts two-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 200 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will break at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, and PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Chinese - Simplified)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Chinese - Simplified OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites:

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/china/downloadDetails/sr2off97.htm.

How the product handles dates:

  • Storage. Microsoft Excel 7 stores dates as numeric values, with day #1 being 1900/01/01. Excel 7 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel 7 formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (YY refers to a 2-digit year), then even when the user types a YYYY date (4-digit year format), it will by default display in a YY format. The date format is customizable. For customers requiring the highest level of assurance concerning the reliability of their date data, we recommend changing the system short date to a YYYY format.
  • Parsing on date entry.
  • If the system date separator matches the date separator used to enter a date with a two-digit year, it will parse to be a 1900 date. For instance if the system date separator is a dash, and the user enters a "yy-m-d" style date, then it will parse as a 1900 date. To reduce ambiguity, enter dates in a YYYY-M-D format.
  • If the system date separator does not match the date separator used to enter a date with a two digit year, it will parse such that a year less than 20 is 20XX, and equal to or greater than 20 is 19XX. For instance if the system date separator is a dash, and the user enters a "yy/m/d" style date such as 25/1/1, it will parse to 01-JAN-1925. To reduce ambiguity, enter dates in a YYYY/M/D format.
  • On a default Chinese Simplified system, if a user enters a 21st century date in a "mm/yy/dd" format, some cases will be interpreted as a "yy/mm/dd" format. To reduce ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.

Leap Year. Microsoft Excel 7 treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.

(See Knowledge Base (KB) article Q164406 for more information.)

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Excel 7 might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. This can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base articles Q182766 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.
  • Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q182766 for more information.)
  • Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel 7 assumes "Dec 01" refers to December 1 of the current year. (See Knowledge Base article Q180952 for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Microsoft Excel 7 handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other products.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

File

Various File Formats

  • Don't store 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic / Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel 7.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 7. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 7. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel 7 recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 7 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel 7 treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Chinese - Traditional)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*#
Language: Chinese - Traditional OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 Chinese Traditional by providing software updates for identified issues through January 1, 2001, except for the existing Emperor Dating System issues. Newer Service Packs are also to be maintained at least as Compliant*# with the same Emperor Dating System exception coupled with intent to fix other identified issues, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

An Office 95 Year 2000 update is now available. For more detailed information and to download this update please go to http://www.microsoft.com/taiwan/download/office.htm.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/01/01. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (YY refers to a 2-digit year entry), then even when the user types a YYYY date (4-digit year format), it will by default display in a YYYY format. The date format is customizable. For customers requiring the highest level of predictability concerning their date data, Microsoft recommends changing the system short date to a YYYY format.
  • Parsing on date entry. If a user enters a date in a "yy-M-d" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 95 will recognize, "15-01-01" as January 1, 2015, but will recognize "25-01-01" as January 1, 1925. To avoid any possible confusion, however, users can display dates in a YYYY format so the century is clearly shown.
  • If a user enters a date in a "yy/mm/dd" format, it will be interpreted as a Republic of China era date. For instance, "1/2/3" will parse to 03 FEB 1912. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.
  • On a default Chinese Traditional system, if a user enters a 21st century date in a "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.
  • Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.

(See Knowledge Base (KB) article Q164406 for more information.)

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Excel 7 might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 1926 (R.O.C. era 15, January 1). Such a change can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files.
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.
  • Recording date entry in a macro records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q182766 for more information.)
  • Using a format such as "Dec 98" or "12/98" is not interpreted at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel 7 assumes "Dec 01" refers to December 1 of the current year. (See Knowledge Base article Q180952 for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Microsoft Excel 7 handles serial dates with the highest degree of accuracy. Due to the ambiguous nature of text dates, in general they will have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025 or Feb. 1, 1936 (R.O.C. era 25, Feb. 1)
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other products.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

File

Various File Formats

  • Don't store 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To resolve, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. In general, importing 2-digit dates will be parsed as R.O.C. era dates. They will parse as Gregorian dates with a 2019/1920 cutoff when the separator used for date entry is different from system setting (Ex: Date entry is 05-01-01 and date separator of system setting is "/" in the Control Panel – Regional Settings). This is different from later versions of Excel, so use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • In general, date entries will be parsed as R.O.C. era dates first. They will be parsed as Gregorian dates with a 2019/1920 cutoff when the separator used for date entry is different from system setting (Ex: Date entry is 05-01-01 and date separator of system setting is "/" in the Control Panel-Regional Settings).

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic / Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel 7.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 7. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 7. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel 7 recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 7 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Czech)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Czech OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Danish)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Danish OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Dutch)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Dutch OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System Clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (English)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: English OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above
Clock Dependencies: System Clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Finnish)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Finnish OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above
Clock Dependencies: System Clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (French)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: French OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (German)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: German OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Greek)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Greek OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System Clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Hebrew)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant#
Language: Hebrew OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Hebrew Windows 95/98 in both enabled and localized versions,
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

What are the acceptable deviations?
MS Query accepts 2-digit year date formatting for the user’s ODBC query, but assumes a date in the 1900s. To avoid this issue, users should use 4-digit years for queries based upon date data.

Special Notes for Hebrew version of Excel:

  • Hebrew Excel 95 supports Hebrew Lunar calendar.
  • Hebrew Excel 95 has the ability to parse a date into lunar Hebrew date. Day one of Gregorian (01/01/01 A.D.) is equivalent to 06-Tavis -3761 in Hebrew.
  • Hebrew Excel 95 will try to format the date entered in a cell based on what the Short Date Style has been set to in the Control Panel and in Gregorian calendar, even if the calendar in Control Panel has been set to Hijri.

  • Hebrew Excel 95 also has the ability to format a Gregorian date into a Hebrew date by appending the string "B2" to the beginning of the format type, e.g. applying the format B2mm/dd/yy to the Gregorian date 12/31/98 in Hebrew Excel results in the Hebrew date 12-Tavis-5759. The "B2" string is applied in the Format Cells dialog, Number tab/Custom or using the NumberFormat property of the Range object using Visual Basic for Applications.
  • To convert back a Hebrew date back into Gregorian, the "B2" prefix is omitted.

 

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/1/1. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. If the system short date is a YYYY (4-digit year) format, when the user types a YY date (a 2-digit year entry), it will by default display in a YYYY format. Excel 95 adds 1900 or 2000 (based on 1920 cutoff) to 2-digit years. What this means is that 2-digit years that fall in the 00-19 range will be recognized as 2000-2019, while those 2-digit years that fall in the 20-99 range will be recognized as 1920-1999. When a cell is formatted with the B2 prefix Hebrew Excel 95 adds the year 5700 to a date with 2-digit year.
  • Parsing on date entry. If a user enters a date in a Gregorian "yy-m-d" format, 00-19 is 20XX, and 20-99 is 19XX.

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, a user has the date January 1, 1915. The user copies the date, but the system settings are "M/d/yy", and the text that is copied is "1-1-15". When the user pastes "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. The user cannot pass the DATE()function Hebrew year, month and day. Even if the cell is formatted with B2 prefix, Hebrew Excel 95 will calculate the Gregorian date based on the parameters passed to it and then will convert the date to the Hebrew Lunar Calendar.
  • Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 <http://support.microsoft.com/support/kb/articles/Q180/9/52.asp> for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Recording date entry in a macro records the year in a YY (2-digit year) format, which can cause problems if the 2-digit year is not meant to follow the 1920-2019 date cutoff window that is mentioned above.
  • Since Visual Basic for Applications macro recorder uses English settings only, and not Regional Settings, and since Hebrew Excel parses Lunar dates based on custom format and not based on the system calendar, it is not possible to have the recorder record a Hebrew date entry.
  • Due to the ambiguous nature of text dates, use serial dates whenever possible and take great care when transferring text dates.

Recommendations:

    • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
    • To avoid confusion or miscalculations, Hebrew Excel 95 users should maintain a single type of date representation on the same sheet. If a user decides to use Hebrew dates, then they should use only Hebrew dates.
    • Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y may experience miscalculations. It is highly recommended to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products are difficult to predict. Interoperability testing with other Microsoft Office products can be conducted safely.

Testing

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If the user decides not to set the system short date format to include a 4-digit year, the user can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Hebrew Excel 95 transitions smoothly into the year 2000 when the Locale in Regional Settings is set to Hebrew: Warning! Before conducting this test, make sure you do not have software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999 and then format the cell into B2dd/mm/yyyy. Start Hebrew Excel 95. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the date shown will be 22/04/5760 Hebrew Lunar and nothing unusual has happened to Microsoft Excel. Remember to reset the system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.

 

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Hungarian)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Hungarian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Italian)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Italian OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 01 Jan 1900
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Japanese)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*#
Language: Japanese OS: 32-Bit Win Release Date: 07 Nov 1995
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System cllock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 Japanese by providing software updates for identified issues through January 1, 2001, except for the existing Emperor Dating System issues. Newer Service Packs are also to be maintained at least as Compliant*# with the same Emperor Dating System exception coupled with intent to fix other identified issues, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

An Office 95 Year 2000 update is now available. For more detailed information and to download this update please go to http://www.microsoft.com/japan/Office/OfficeFreeStuff/Office/O95y2k/.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/01/01. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. If the system short date is a YY format (YY refers to a 2-digit year entry), then even when the user types a YYYY date (4-digit year entry), it will by default display in a YY format.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Microsoft Excel 95 will recognize, 15-01-01" as January 1, 2015, but will recognize "25-01-01" as January 1, 1925. To avoid possible confusion, however, users can always display dates in a YYYY format so the century is clearly shown.

If a user enters a date in a "yy/mm/dd" format, it will be interpreted as a Japanese era date. For instance, "1/2/3" will parse to 03 FEB 1989, or February 3, Heisei year 1. To avoid ambiguity, enter dates in a YYYY/MM/DD format so they can be clearly understood as Gregorian dates. Or enter dates with a prefix for the Japanese era, such as H, S, T, or M, so they can be understood as Japanese era dates.

On a default Japanese system, if a user enters a 21st century date in a "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.

  • Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

Two-digit shortcut handling:

See discussion above.

(See Knowledge Base (KB) article Q164406 for more information.)

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel 7 might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1-1-15". When you paste "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q182766 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.
  • Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q182766 for more information.)
  • Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel 7 assumes it is a year. However, Microsoft Excel 7 assumes "Dec 01" refers to December 1 of the current year. (See KB article Q180952 for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Microsoft Excel handles serial dates with the highest degree of accuracy. Due to the ambiguous nature of text dates, in general they will have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2-digit format is used for the year. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Excel 7 within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, or PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4-digit dates (for the year) to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic / Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 7. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 7. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel 7. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 7 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel 7 treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Korean)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Korean OS: 32-Bit Win Release Date: 01 May 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites


An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to
http://officeupdate.microsoft.com/articles/O95y2kfactsheet.htm.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/01/01. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (YY refers to a 2-digit year entry), then even when the user types a YYYY date (4-digit year), it will by default display in a YY format. The date format is customizable. For customers requiring the highest level of assurance concerning the reliability of their date data, we recommend changing the system short date to a YYYY format.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" or "yy/mm/dd" format, it will parse to be a 1900 date, except for the year "00" which parses to 2000. To avoid ambiguity, enter dates in a YYYY-M-D or YYYY/M/D format.
  • On a default Korean system, if a user enters a date in an "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.
  • Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes that two-digit years are 20th century (19XX), except for the year "00" which parses to 2000.

(See Knowledge Base (KB) article Q164406 for more information.)

Common date usage errors:

  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.
  • Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q182766 for more information.)
  • Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel 7 assumes it is a year. However, Microsoft Excel 7 assumes "Dec 01" refers to December 1 of the current year. (See Knowledge Base article Q180952 for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • Defined names store references as text strings. Since they do not store dates as serial values, they are susceptible to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience misinterpretations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify dates are being properly used. The table below can be used to guide testing of Excel 7 within your organization.

Sub-system

Component

File

Various File Formats

  • Don't store 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates will be parsed such that dates are 20th century (19XX)_, except for the year "00" which parses to 2000. This is different from later versions of Excel, so use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse such that all dates are 20th century (19XX), except for the year "00" which parses to 2000.
  • Date entry will parse such that all dates 19XX, except for the year "00" which parses to 2000.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic/ Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel 7.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network so it is highly recommended that you isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel 7. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel 7. Remember to reset your system clock to the correct time and date after conducting this test.
  • Verify that Excel 7 recognizes the year 2000 as a leap year: Start Microsoft Excel 7. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel 7 correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel 7 treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Norwegian)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Norwegian OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Polish)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Polish OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Portuguese (Brazil))

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Portuguese (Brazil) OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System Clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Russian)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Russian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Slovenian)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant+
Language: Slovenian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: None
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

An Office 95 Year 2000 software update will be available in June 1999 that will correct known Year 2000 related issues in the applications used in Office 95. For specific issues remediated by this software update see http://officeupdate.microsoft.com/articles/O95y2kfactsheet.htm

 

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is always some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Spanish)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*
Language: Spanish OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above.
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Swedish)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant*+
Language: Swedish OS: 32-Bit Win Release Date: 08 Jan 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: Office 95 Year 2000 Software Update
Product Dependencies: Microsoft Windows 95 or above or Microsoft Windows NT 3.51 or above
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 95 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites

An Office 95 Year 2000 update is now available that corrects all known Year 2000 related issues in the applications used in Office 95. For more detailed information and to download this update please go to http://officeupdate.microsoft.com/Articles/o95y2kinternational.htm.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 95 recognizes 01-JAN-1900 through 31-DEC-2078 as valid dates. 01/01/2000 is stored as value 36526, since it is the 36526th day in the century.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format (refers to a 2-digit year entry), then even when the user types a YYYY (refers to a 4-digit year entry) date, it will by default display in a YY format. The format can be changed. To avoid any ambiguity we recommend changing the system short date to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 20 is 20XX, and equal to or greater than 20 is 19XX. For example, Excel 5 will recognize, "01/01/15" as January 1, 2015, but will recognize "01/01/25" as January 1, 1925. To avoid any possible confusion, users can always display dates in a YYYY format so the century is clearly shown.

Leap Year. Microsoft Excel treats 1900 as a leap year for backward compatibility with other products such as Lotus 1-2-3. (See Knowledge Base article Q181370 for more information.)

2-digit shortcut handling:
See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1920 through 2019.
(See
Knowledge Base (KB) article Q164406 for more information.)

What are the acceptable deviations?
MS Query accepts 2-digit-year date formatting for your ODBC query, but will assume a date in the 1900s. To avoid this issue, you should always use 4-digit years for queries based upon date data. After applying the Office 95 year 2000 software update, MS Query 2.0 (Msqry32.exe) uses a different rule for 2-digit years. Years entered as 00-29 are assumed to be in the range 2000 through 2029. Years entered as 30-99 are assumed to be in the range 1930 through 1999.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See KB article Q180159 for more information.)

Using a format such as "Dec 98" or "12/98" will not be interpreted correctly at the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Microsoft Excel handles serial dates, the most common usage of dates, properly. Due to the ambiguous nature of text dates, there is some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines and recommendations:
In general, avoid testing in a production environment or with non-duplicated production files because we cannot predict side effects with other products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Excel within your organization.

Sub-system

Component

 

File

Various File Formats

Don't store 2Y dates in text file formats such as TXT, DIF, CSV, or PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2019/1920 cutoff. This is different from later versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2019/1920 cutoff rule. Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions
Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Excel recognizes the year 2000 as a leap year: Start Microsoft Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice that Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

 

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Thai)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant#
Language: Thai OS: 32-Bit Win Release Date: 11 Mar 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: none
Product Dependencies: Microsoft Thai Windows 95/98 or Thai Windows NT 4
Clock Dependencies: System Clock
Last Updated: 12 Nov 1999
Product Details

What are the issues with this product?
MS Query accepts 2-digit year date formatting for the user’s ODBC query, but assumes a date in the 1900s. To avoid this issue, users should use 4-digit years for queries based upon date data.

Special Notes for Thai version of Excel:

  • Thai Excel 95 supports the Buddhist calendar. Serial date 1 corresponds to January 1, 1900 in the Gregorian calendar and January 1, 2443 in the Buddhist calendar. The only difference between Buddhist and Gregorian dates is that Buddhist year number is 543 larger than the Gregorian.
  • Thai Excel 95 will parse the date entered in a cell according to the Short Date Style set in the Regional Settings of the Control Panel using the Gregorian calendar, even if the Calendar Type has been set to Buddhist.
  • A date in a cell can be expressed either as Buddhist or Gregorian by adjusting the cell format in the Format Cells dialog, on the Number tab, in the Custom category. Replacing yy with bb or yyyy with bbbb causes the date to be expressed with a 2- or 4-digit Buddhist year. Suppose the date May 15, 1998 (serial date 35930) is entered in a cell. Formatting the cell as d/m/yy will show 15/5/98, d/m/yyyy will show 15/5/1998, d/m/bb will show 15/5/41, and d/m/bbbb will show 15/5/2541.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1/1/1900. The day number for any date in history stays the same regardless of whether cell displaying the date is formatted Gregorian or Buddhist. Excel 95 recognizes 01-Jan-1900 through 31-Dec-2078 as valid dates. Visual Basic /Visual Basic for Applications use the same serial date system, with the exception of 1-Jan-1900 through 28-Feb-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. December 31, 1999 is stored as day #36525 in Excel even though there are only 36524 days in the 1900s.
  • 2-Digit year entries. Excel adds 1900 or 2000 to 2-digit year entries so that all such entries will be stored as years between 1920 and 2019, inclusive. This will be called the 2019/1920 cutoff rule.

00 to 19 is interpreted as 20xx (2000 to 2019)

20 to 99 is interpreted as 19xx (1920 to 1999)

  • Formatting. Excel 95 will format the date entered in a cell according to the Short Date Style set in the Regional Settings of the Control Panel. If the system short date is a yyyy (4-digit year) format, when the user types a yy date (2-digit year format), it will by default display in a yyyy format according to the 2019/1920 cutoff rule.

Common Date Usage Errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, the user has the date January 1, 1915. When copying the date, the system settings are "M/d/yy", and the text that is copied is "1-1-15". When the user pastes "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such a misinterpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)

  • The DATE() function is not designed to take 2-digit year shortcuts since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if the user were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. 
  • Recording date entry in a macro records/plays back the year in yy format even if the user enters yyyy and even if the system short date format was yyyy. For example if the system date was MM/dd/yyyy and the user records a macro which enters in a cell the date 12/12/2025, Thai Excel 95 will play it back as 12/12/1925. This may cause problems if the 2-digit year is not meant to follow the 1920-2019 date window that is mentioned above. See Knowledge Base article Q180159 for more information.
  • Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 <http://support.microsoft.com/support/kb/articles/Q180/9/52.asp> for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Recommendations:

  • Due to the ambiguous nature of text dates, use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/15" could be interpreted as Feb. 1, 1915, Jan. 2, 1915, Feb. 1, 2015, or Jan. 2, 2015.
  • In order to avoid confusion or miscalculations, users should stick with one type of date representation on the same sheet. If a user decides to use Buddhist date formats, then they should stick with Buddhist.
  • Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines:

    • In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products are difficult to predict. Interoperability testing with other Microsoft Office products can be conducted safely.
    • The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates will be parsed with the 2019/1920 cutoff. Use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic/Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing:

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If the user decides not to set the system short date format to include a 4-digit year, the user can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Thai Excel 95 transitions smoothly into the year 2000 when the Locale in Regional Settings is one of the Thai countries: Warning! Before conducting this test, make sure there is not software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that the user isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Thai Excel 95. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be January 1, 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset the system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 95  7.0   (Vietnamese)

Product Summary
Product: Excel 95 Version: 7.0 Category:Compliant#
Language: Vietnamese OS: 32-Bit Win Release Date: 10 Sep 1996
Operational Range: 01 Jan 1900 - 31 Dec 2078
Prerequisites: none
Product Dependencies: Microsoft Vietnamese Windows 95
Clock Dependencies: System Clock
Last Updated: 12 Nov 1999
Product Details

What are the issues with this product?
MS Query accepts 2-digit year date formatting for the user’s ODBC query, but assumes a date in the 1900s. To avoid this issue, users should use 4-digit years for queries based upon date data.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1/1/1900. The day number for any date in history stays the same regardless of the format in which the date is displayed. Excel 95 recognizes 01-Jan-1900 through 31-Dec-2078 as valid dates. Visual Basic/Visual Basic for Applications use the same serial date system, with the exception of 1-Jan-1900 through 28-Feb-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. December 31, 1999 is stored as day #36525 in Excel even though there are only 36524 days in the 1900s.
  • 2-Digit year entries. Excel adds 1900 or 2000 to 2-digit year entries so that all such entries will be stored as years between 1920 and 2019, inclusive. This will be called the 2019/1920 cutoff rule.

00 to 19 is interpreted as 20xx (2000 to 2019)

20 to 99 is interpreted as 19xx (1920 to 1999)

  • Formatting. Vietnamese Excel 95 will format the date entered in a cell according to the Short Date Style set in the Regional Settings of the Control Panel. If the system short date is a yyyy (4-digit year) format, when the user types a yy date (2-digit year format), it will by default display in a yyyy format according to the 2019/1920 cutoff rule.

Common Date Usage Errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, the user has the date January 1, 1915. When copying the date, the system settings are "M/d/yy", and the text that is copied is "1-1-15". When the user pastes "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such a misinterpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if the user were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. 
  • Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 <http://support.microsoft.com/support/kb/articles/Q180/9/52.asp> for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Recording date entry in a macro records/plays back the year in yy format even if the user enters yyyy and even if the system short date format was yyyy. For example if the system date was MM/dd/yyyy and the user records a macro which enters in a cell the date 12/12/2025, Vietnamese Excel 95 will play it back as 12/12/1925. This may cause problems if the two-digit year is not meant to follow the 1920-2019 date window that is mentioned above. See Knowledge Base article Q180159 for more information.

Recommendations:

  • Due to the ambiguous nature of text dates, use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/15" could be interpreted as Feb. 1, 1915, Jan. 2, 1915, Feb. 1, 2015, or Jan. 2, 2015.
  • Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Testing guidelines:

    • In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products are difficult to predict. Interoperability testing with other Microsoft Office products can be conducted safely.
    • The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates will be parsed with the 2019/1920 cutoff. This is different from previous versions of Excel, so use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse according to the 2019/1920 cutoff rule.
  • Date entry will parse according to the 2019/1920 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic/Visual Basic for Applications

Transfer between VB/VBA and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing:

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are always stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid any ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If the user decides not to set the system short date format to include a 4-digit year, the user can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Vietnamese Excel 95 transitions smoothly into the year 2000 when the Locale in Regional Settings is one of the Vietnamese countries: Warning! Before conducting this test, make sure there is not software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that the user isolate the computer from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Vietnamese Excel 95. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be January 1, 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset the system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 95 uses a number of Microsoft Office 95 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 95, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 95 Microsoft Office document.

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Arabic)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*#
Language: Arabic OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: MSQuery software update
Product Dependencies: Arabic Windows 95/98 in both enabled and localized flavors, Arabic Windows NT 4 Enabled
Clock Dependencies: System clock
Last Updated: 17 Sep 1999
Product Details

Prerequisite for Year 2000 Compliance—MSQuery Patch:

To resolve known issues with Excel 97 Arabic, Microsoft Query must be updated (see Knowledge Base article Q187698 – MSQuery uses 1900 date when two digits are used for year in a query). This issue is addressed for the English version of Excel 97 in Service Release 2. Since this Service Release is not presently available for the Arabic version it is recommended that the software update be applied to address the issue in the Arabic version of Excel 97. To do this the user will need to download the following files into the Office folder from

http://www.microsoft.com/middleeast/support/kb/68.stm

Msqry32.exe

Qryint32.dll

Msqry32.aw

Msqry32.cnt

Msqry32.hlp

Special Note for Arabic versions of Excel:

 Arabic Excel 97 supports Hijri calendar.

 Arabic Excel 97 has the ability to parse a date in Hijri date format. Day one of Hijri (01/01/01) is equivalent to July 16, 622 AD.

 In most countries in the Middle East region, the popular date format is dd/mm/yy or dd/mm/yyyy. Arabic Excel 97 will try to format the date entered in a cell based on what the Short Date Style has been set to in the Control Panel and in Gregorian calendar, even if the calendar in Control Panel has been set to Hijri. Arabic Excel 97 also has the ability to format a Gregorian date into a Hijri date by appending the string "B2" to the beginning of the format type, e.g. applying the format B2mm/dd/yy to the Gregorian date 12/31/98 in Arabic Excel results in the Hijri date 09/13/19, where 19 is the YY representation for year. The "B2" string is applied in the Format Cells dialog, Number tab/Custom or using the NumberFormat property of the Range object using Visual Basic for Application.To convert back a Hijri date back into Gregorian, the "B2" prefix is omitted.

 Some Arabic countries in the Middle East use one of the following calendar types besides Hijri: Arabic Gregorian, Arabic Transliterated Gregorian, French Gregorian, and French Transliterated Gregorian. The date formats mentioned above are Gregorian and the only difference is the name of the month would be in Arabic, French, Arabic Transliterated or French Transliterated. Arabic Excel 97will apply the above format to a date based on what country is selected in the Regional Settings and since these formats are Gregorian, there is no need for the B2 prefix.

 Even though the country selected might default to a non-English Gregorian calendar, when the user types into a cell a string with the format mmm, Arabic Excel 97 automatically parses the date with a B1 prefix to force the month to appear in Gregorian English. The user can switch the month name from English to the default (Arabic, Transliterated Arabic, French, Transliterated French) by taking out the B1 prefix.

 When a date prior to Jan 1, 1900 is entered in a cell, Arabic Excel 97 converts the date into Hijri automatically. In other words the date 12/28/1887 remains unparsed in US Excel 97 it gets the custom format B2mm/dd/yyyy with Arabic Excel 97.

 Hijri dates come with 29 or 30 days. When the user enters a date with the format B2 and with day 30, but that particular Hijri month happened to have 29 days only, Arabic Excel 97 will bump the date to the 1st day of the following month.

 

 

How the product handles dates:

For all Arabic Office 97 applications and with the exception of Outlook 97, if the user enters a date that uses a two-digit year in the Custom tab of the Properties dialog box, the date will be formatted with a value between 1900 - 1999. As an example the user does the following:

Selects Properties or Database Properties from the File menu.

Clicks the Custom tab.

Enters a field name in the Name edit box.

Selects date from the Type list.

Enters the value 7/5/00 in the value field.

Clicks Add.

The date will appear in the properties list box as 7/5/1900, not 7/5/2000. For information check the Knowledge Base Article Q186261.

    • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/1/1. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. Visual Basic /Visual Basic for Applications use the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.
    • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. If the system short date is a YYYY (4-digit year) format, when the user types a YY date (2-digit year format), it will by default display in a YYYY format. Just like US Excel adds 1900 or 2000 (based on 1930 cutoff) to 2-digit years, when a cell is formatted with the B2 prefix, Arabic Excel 97 adds the Hijri year 1400 to 2-digit years.
    • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. Gregorian 12/31/2029 is equivalent to Hijri 08/25/1451, and Gregorian 01/01/1930 is equivalent to 08/01/1348. So from a Hijri date point of view, Arabic Excel 97 does not obey the "< 30 = 20XX" rule. This design is expected, as the year 2000 in Hijri does not occur for another 6 centuries. For example if you format a cell as B2mm/dd/yy, then type in the cell the Hijri date 8/1/48, Excel will parse this as 08/01/1448.
    • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 97 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit-year format, a solution is to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling:

See the preceding discussion. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029. For more information, see Knowledge Base (KB) article Q164406.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel parses the date to January 1, 2015. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. For more information, see KB article Q180159.
  • The DATE() function is not designed to take 2-digit year shortcuts since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if the user were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. The user cannot pass the DATE()function Hijri year, month and day. Even if the cell is formatted with B2 prefix, Arabic Excel 97 will take calculate the Gregorian date based on the parameters passed to it and then will convert the date to Hijri. For example if the user formats a cell as B2mm/dd/yyyy and then types in it "=DATE(15,1,1)", the user will get 02/15/1333. Excel looks at the parameters passed to DATE() and considers that as 01/01/1915 and then it converts to Hijri.

 Recording date entry in a macro records/plays back the year in YY format even if the user enters YYYY and even if the system short date format was YYYY. For example if the system date was MM/dd/yyyy and the user enters in a cell 12/12/2030, Arabic Excel 97 will play it back as 12/12/1930. This may cause problems if the two-digit year is not meant to follow the 1930-2029 date window that is mentioned above. See Knowledge Base article Q180159 for more information.

 Since Visual Basic for Applications macro recorder uses English settings only and not Regional Settings and since Arabic Excel parses Hijri dates based on custom format and not based on the system calendar, it is not possible to have the recorder record a Hijri date entry.

  • Using a format such as "Dec 98" will not function properly at the year 2001. Because 98 is too large to be a day of the month, Excel assumes it is a year. However, Excel assumes "Dec 01" is December 1 of the current year. Because Excel always stores the complete date, users can avoid ambiguity by entering a full date, regardless of the display formatting. For more information, see KB article Q180952.
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015.
  • Due to the ambiguous nature of text dates, in general they will always have some potential for error. Whenever possible, use serial dates and take great care when transferring text dates.
  • When dates must be transferred between programs, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as February 1, 1925; January 2, 1925; February 1, 2025; or January 2, 2025. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit-year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date.
  • For Arabic Excel 97 and in order to avoid confusion or miscalculations, users should stick with one type of date representation on the same sheet. If a user decides to use Hijri, then they should stick with Hijri, or if they decide to use Gregorian, they should stick with Gregorian.
  • Arabic Excel 97 will not display in a worksheet cell the date for the 1st of January for the first leap year following a non-leap century year. Enter "1-Jan-2104"… the cell will display "1-Feb-2104". Note that 2100 is a century year, but not a leap year, and 2104 is the first leap year following. Though the date appears wrong in the cell, the serial value stored in memory is correct and calculations based on the date should be accurate. See KB article Q175362 for more information.

 

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year--which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change all date formats in a workbook to formats that display all 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.
  • The Date Watch Wizard runs in the background while users work in Excel. It suggests alternatives when ambiguous text dates are entered in cells or functions, changes number formats to 4-digit years when 2-digit years are entered, and displays an alert when text files that contain 2-digit years are opened.

For more information about these add-in tools, see KB article Q176943.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with nonduplicated production files because side effects with other noncompliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The following table can be used to guide testing of Excel within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as TXT, DIF, CSV, PRN.
The default column width with default fonts may truncate characters with date formats that have eight digits and two separators. To correct this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources

Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from previous versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions

Date entry

Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic/Visual Basic for Applications (VB/VBA)

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to the wrong century. This may also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Excel has been designed for calculations in the year 2000 and beyond. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Users who work with dates will benefit from changing the system short date format to one that uses a 4-digit year (for example, "MM/dd/yyyy"). This change allows the user to clearly see the century of a date. Conducting the tests below is only worthwhile if 4-digit years are used. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit-year format.

To change the system short date format, do the following. On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

 

  • Test 1--Verify that Arabic Excel transitions smoothly into the year 2000:

    Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired, it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 P.M., December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 1 minute, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test. Repeat the test with the Hijri date 9/24/1420 and with Calendar set to Hijri in Control Panel/Regional Settings.

 

  • Test 2--Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes 2000 as a leap year.

Note: The year 1900 is not a leap year; however, in your testing you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by 4, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. For more information, see KB article Q181370.

  • Test 3-- Verify that Arabic Excel 97 parses dates before Jan 1, 1900 to Hijri.

Make sure the system's Short Date is dd/mm/yyyy or dd/mm/yy. With Arabic Excel, type the date "5/7/1877" in a cell and hit Enter. Press Ctrl + 1 to see the formatting of the cell. Make sure the format has the prefix B2. Also make sure to cover boundary lines like what happens at 31/12/1899.

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Canadian French)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Canadian French OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Chinese - Simplified)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Chinese - Simplified OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98 or Windows NT 3.51 with Service Pack 5 or greater, or Windows NT 4 (no specific Service Pack is required, though Service Pack 2 is recommended)
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

 

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Office 97 Service Release 2 (SR-2) is required for Year 2000 compliance. SR-2 can be downloaded from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Notes for East Asian versions of Excel

  • East Asian versions of Excel 97 Service Release-2 (SR-2) include a new method for parsing Gregorian dates. The new behavior is optimized to be the easiest way to deal with dates in the 2000s. East Asian versions of Excel 97 SR-2 also contain the old method for parsing Gregorian dates.
  • The default setting for Chinese Simplified Excel 97 SR-2 is the new method for parsing Gregorian dates.
  • To switch between the two date-parsing behaviors, look on the SR-2 CD under \Valupack\XLParse for the following two files: "Newparse.reg" and "Oldparse.reg." If you have upgraded to Office 97 SR-2 by using the downloadable update, these two files are located on the hard drive in the \Office folder, which is usually found under \Program Files\Microsoft Office. Double clicking a file sets a registry key so that the next time Excel starts up, it is in the desired date-parsing mode.
  • In this document, any reference tagged with (Old Date-Parsing Mode) applies both to Excel 97 SR-2 in the old parsing mode and to Excel 97 SR-1 and earlier versions of Excel 97. References not tagged with (Old Date-Parsing Mode) apply to the new date-parsing mode found in SR-2.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 1900/01/01. Excel 97 recognizes 1900/01/01 through 9999/12/31 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 1900/01/01 through 1900/02/28, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3, which treats 1900 as a leap year. Previous versions of Excel recognize 1900/01/01 through 2078/12/31 as valid dates.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a "yy" format ("yy" refers to a 2-digit year), then even when the user types a 4-digit-year (yyyy) date, it will by default display in a 2-digit-year (yy) format. The date format is customizable. For customers requiring the highest level of assurance concerning the reliability of their date data, it is recommended that users change the system short date to a "yyyy" format.
  • Parsing on date entry. If a user enters a date in a "yy/m/d" or "yy-m-d" format, a number less than 30 is assumed to be the year 20xx, while a number equal to or greater than 30 is assumed to be the year 19xx. For example, 25/1/1 parses to January 1, 2025. To avoid confusion and to show the century clearly, it is recommended that users display dates in a "yyyy" format.

    (Old Date-Parsing Mode) If the system date separator matches the date separator used to enter a date with a 2-digit year, it will parse to a 1900 date. For example, if the system date separator is a dash and the user enters a date in a "yy-m-d" format, then it will parse to a 1900 date. To avoid ambiguity, dates should be entered in a "yyyy-m-d" format.

    (Old Date-Parsing Mode) If the system date separator does not match the date separator used to enter a date with a 2-digit year, it will parse such that a number less than 30 is assumed to be the year 20xx, while a number equal to or greater than 30 is assumed to be the year 19xx. For example, if the system date separator is a dash and the user enters a date in a "yy/m/d" format, such as 25/1/1, it will parse to January 1, 2025. To avoid ambiguity, dates should be entered in a "yyyy/m/d" format.
  • (Old Date-Parsing Mode) On a default Chinese Simplified system, if a user enters a date from the 2000s in an "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, dates should be entered in a "yyyy/mm/dd" format so that the date can be clearly understood.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. The East Asian Date Migration Wizard, discussed under "Common date usage errors," will be available soon to help the user identify and correct these situations.

Two-digit shortcut handling:

See the preceding discussion. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date, January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel parses the date to January 1, 2015. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. For more information, see Knowledge Base article Q180159.
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015.
  • Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. For more information, see Knowledge Base article Q180159.
  • Using a format such as "Dec 98" or "12/98" will not function properly at the year 2001. Because 98 is too large to be a day of the month, Excel assumes it is a year. However, Excel assumes "Dec 01" is December 1 of the current year because 01 is small enough to be interpreted as a day of the month. For more information, see Knowledge Base article Q180952.
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Due to the ambiguous nature of text dates, in general they will always have some potential for error. Whenever possible, use serial dates and take great care when transferring text dates.
  • When dates must be transferred between programs, ideally, they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as February 1, 1925; January 2, 1925; February 1, 2025; or January 2, 2025. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit-year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date.

Microsoft is creating the following add-in tool to help users identify Year 2000 issues in solutions created in Excel 97:

  • The East Asian Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates. The wizard will be available at the Microsoft web site shortly. This document will be updated with the hyperlink to the wizard when it is available.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The following table can be used to guide testing of Excel within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as TXT, DIF, CSV, or PRN.
The default column width with default fonts may truncate characters with date formats that have eight digits and two separators. To correct this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources

Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from previous versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions

Date entry

Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic/Visual Basic for Applications (VB/VBA)

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to the wrong century. This may also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit-year format.

To change the system short date format, do the following: On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

  • Test 1--Verify that Excel transitions smoothly into the year 2000:

    Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired, it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 P.M., December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 1 minute, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2--Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes 2000 as a leap year.

Note: The year 1900 is not a leap year; however, in your testing you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by 4, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. For more information, see Knowledge Base article Q181370.

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Chinese - Traditional)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Chinese - Traditional OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers’ Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisite: Download the Office 97 Service Release 2 (SR2) patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

 

Special Note for East Asian versions of Excel:

  • East Asian versions of Excel 97 SR-2 include a new method for parsing Gregorian dates. The new behavior is optimized to be an easy way to deal with 21st century dates. In addition, East Asian versions of Excel 97 SR-2 also contain the old method for parsing Gregorian dates.
  • The default setting for Chinese Traditional Excel 97 SR-2 is the old method for parsing Gregorian dates.
  • To switch between the two date parsing behaviors, look on the SR-2 CD under \Valupack\XLParse for two files: "Newparse.reg" and "Oldparse.reg". Double clicking the file sets a registry key so that the next time that Excel starts up, it is in the desired date parsing mode.
  • In this compliance document, references tagged with (OLD DATE PARSING MODE ONLY) applies both to Excel 97 SR-2 in the old parsing mode, and also to Excel 97 SR-1 and earlier versions of Excel 97. References not tagged with (OLD DATE PARSING MODE ONLY) can be assumed to apply to the new date parsing mode in SR-2.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/1/1. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. Visual Basic/Visual Basic for Applications uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of backward-compatibility issues with Lotus 1-2-3, which treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY (2-digit year) format, then even when the user types a YYYY (4-digit year format) date, it will by default display in a YYYY format. The date format is customizable. For customers requiring the highest level of predictability concerning their date data, it is recommend they change the system short date to a YYYY format.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "25-1-1" used to parse to 01-JAN-1925, but with SR 2 now parses to 01-JAN-2025. To avoid ambiguity, display dates in a YYYY format so the century is clearly shown.
  • (OLD DATE PARSING MODE ONLY). If a user enters a date in a "yy/mm/dd" format, it will be interpreted as a R.O.C. era date. For instance, "1/2/3" will parse to 03 FEB 1912. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.
  • (OLD DATE PARSING MODE ONLY). On a default Chinese Traditional system, if a user enters a 21st century date in a "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. The Date Migration Wizard, an Excel add-in, will be available shortly to aid the user in identifying and correcting these situations.

 

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, the user has the date January 1, 1915. The user copies the date, but the system settings are "M/d/yy", and the text that is copied is "1/1/15". When pasted "1/1/15" into Microsoft Excel, it will parse the date to January 1, 1926 (R.O.C. era 15, January 1). Such a change can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files.
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) were entered, the resulting date would be January 1, 1915, not 2015. Increasing the numeric parameters can yield 20xx dates.
  • Recording date entry in a macro records the year according to the system short date format, which results in parsing a 2-digit year in playback. (See Knowledge Base article Q180159 for more information.)
  • Using a format such as "Dec 98" or "12/98" will not be interpreted at the year 2001. This is because 98 is too large to be the day of month so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year as 01 is small enough to be interpreted as a day of the month. Excel assumes the user has entered a valid date and works to match it to the most likely valid date (See Knowledge Base article Q180952 for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Due to the ambiguous nature of text dates, in general they will have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "25/2/1" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, Jan. 2, 2025, or Feb. 1, 1936 (R.O.C. era 25, Feb. 1).
  • Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a two-digit format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Microsoft has created an add-in tool to help users identify Year 2000 issues in solutions created in Microsoft Excel97:

  • The East Asian Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates. The East Asian Date Migration Wizard is available on the Microsoft web site.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To resolve, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. With the old date parsing mode, the behavior is the same as in previous versions. With the new date parsing mode, importing 2-digit dates will be parsed with the 2029 cutoff. This is different from previous versions of Excel so use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse according to the 2029/1930 cutoff rule.
  • With the old date parsing mode, date entry is the same as previous versions. With the new date parsing mode, date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic/ Visual Basic for Applications

Transfer between Visual Basic/Visual Basic for Applications and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, users should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions smoothly into the year 2000: Warning! Before conducting this test, make sure there is no software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that the computer be isolated from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset the system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, while testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information.)

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Czech)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Czech OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Danish)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Danish OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 01 Jan 1900
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Dutch)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Dutch OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended).
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (English)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: English OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (English)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant#
Language: English OS: Alpha Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: None
Product Dependencies: Windows NT 3.51 with Service Pack 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 12 Nov 1999
Product Details

 

Note: Microsoft Query recognizes 2-digit years as falling in 1900s. For more detailed information on this issue please see the Knowledge Base article Q187698. However, please note that the Office 97 Service Release 2 patch that is mentioned in this Knowledge Base article does not apply to English Excel 97 for Alpha.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 97 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3, which treats 1900 as a leap year.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a "yy" format ("yy" refers to a 2-digit year), then even when the user types a 4-digit-year (yyyy) date, it will by default display in a 2-digit-year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format.
    Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.
  • Parsing on date entry. If a user enters a date in an "M/d/yy" format, a number less than 30 is assumed to be the year 20xx, while a number equal to or greater than 30 is assumed to be the year 19xx. For example, Excel 97 recognizes 01/01/15 as January 1, 2015, and recognizes 01/01/35 as January 1, 1935.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 97 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit-year format, a solution is to change the "yy" date strings to "yyyy" date strings. The Date Migration
    Wizard
    , an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling:

See the preceding discussion. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029. For more information, see
Knowledge Base (KB) article Q164406.

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, the user has the date January 1, 1915. When copying the date, the system settings are "M/d/yy", and the text that is copied is "1-1-15". When the user pastes "1-1-15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an error can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if the user were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.
  • Recording date entry in a macro records/plays back the year in YY format even if the user enters YYYY and even if the system short date format was YYYY. For example if the system date was MM/dd/yyyy and the user enters in a cell 12/12/2030, English Excel 97 Alpha will play it back as 12/12/1930. This may cause problems if the 2-digit year is not meant to follow the 1930-2029 date window that is mentioned above. See Knowledge Base article Q180159 for more information.
  • Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month so Excel 97 assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. (See Knowledge Base article Q180952 for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Recommendations:
  • Due to the ambiguous nature of text dates, use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that does not specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • In order to avoid confusion or miscalculations Excel 97 users should stick with one type of date representation on the same sheet.
  • Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential behaviors.

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year--which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change all date formats in a workbook to formats that display all 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.
  • The Date Watch Wizard runs in the background while users work in Excel. It suggests alternatives when ambiguous text dates are entered in cells or functions, changes number formats to 4-digit years when 2-digit years are entered, and displays an alert when text files that contain 2-digit years are opened.

For more information about these add-in tools, see KB article Q176943.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products are difficult to predict. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

 

File

Various File Formats

Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

 

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2-digit dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4-digit dates to prevent confusion.

 

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

 

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

 

Visual Basic/Visual Basic for Applications

Transfer between Visual Basic/Visual Basic for Applications and cells

Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Finnish)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Finnish OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (French)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: French OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (German)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: German OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Greek)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Greek OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Hebrew)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*#
Language: Hebrew OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: MSQuery software update
Product Dependencies: Hebrew Windows 95/98 in both enabled and localized flavors, Hebrew Windows NT 4 Enabled
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Prerequisite for Year 2000 Compliance—MSQuery Patch:

To resolve known issues with Excel 97 Hebrew, Microsoft Query must be updated (see Knowledge Base article Q187698 – MSQuery uses 1900 date when two digits are used for year in a query). This issue is addressed for the English version of Excel 97 in Service Release 2. Since this Service Release is not presently available for the Hebrew version, it is recommended that the software update be applied to address the issue in the Hebrew version of Excel 97. The software update can be downloaded and installed from the following location:

http://www.microsoft.com/israel/downloads/xl97y2k.exe

 

Msqry32.exe

Qryint32.dll

Msqry32.aw

Msqry32.cnt

Msqry32.hlp

Special Note for Hebrew versions of Excel:

  • Hebrew Excel 97 supports Hebrew Lunar calendar.
  • Hebrew Excel 97 has the ability to parse a date into lunar Hebrew date. Day one of Gregorian (01/01/01 A.D.) is equivalent to 06-Tavis -3761 in Hebrew.
  • Hebrew Excel 97 will try to format the date entered in a cell based on what the Short Date Style has been set to in the Control Panel and in Gregorian calendar, even if the calendar in Control Panel has been set to Lunar Hebrew.
  • Hebrew Excel 97 also has the ability to format a Gregorian date into a Hebrew date by appending the string "B2" to the beginning of the format type, e.g. applying the format B2mm/dd/yy to the Gregorian date 12/31/98 in Hebrew Excel results in the Hebrew date 06-Tavis-5761. The "B2" string is applied in the Format Cells dialog, Number tab/Custom or using the NumberFormat property of the Range object using Visual Basic for Application.
  • To convert back a Hebrew date back into Gregorian, the "B2" prefix is omitted.

 

How the product handles dates:

For all Hebrew Office 97 applications and with the exception of Outlook 97, if the user enters a date that uses a two-digit year in the Custom tab of the Properties dialog box, the date will be formatted with a value between 1900 - 1999. As an example the user does the following:

Selects Properties or Database Properties from the File menu.

Clicks the Custom tab.

Enters a field name in the Name edit box.

Selects date from the Type list.

Enters the value 7/5/00 in the value field.

Clicks Add.

The date will appear in the properties list box as 7/5/1900, not 7/5/2000. For information check the Knowledge Base Article Q186261.

  • Storage. Excel stores dates as numeric values, with day 1 being 01/01/1900. Excel 97 recognizes 01/01/1900 through 12/31/9999 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 01/01/1900 through 02/28/1900, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3, which treats 1900 as a leap year.

Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a "yy" format, then even when the user types a 4-digit-year (yyyy) date, it will by default display in a 2-digit-year (yy) format. Users can avoid this issue by changing their system short date to a "yyyy" format. Just like US Excel adds 1900 or 2000 (based on 1930 cutoff) to 2-digit years, when a cell is formatted with the B2 prefix, Hebrew Excel 97 adds the year 5700 to a date with 2-digit year.

  • Planning for 4-digit-year display is important in programs such as Excel, where columns may be fixed by the worksheet author with widths that are too narrow for 4-digit years.

Parsing on date entry. If a user enters a date in an "M/d/yy" format, a number less than 30 is assumed to be the year 20xx, while a number equal to or greater than 30 is assumed to be the year 19xx. For example, Excel 97 recognizes 01/01/15 as January 1, 2015, and recognizes 01/01/35 as January 1, 1935. Hebrew Excel 97 uses Hebrew characters to represent digits so the 1930 cutoff date would not apply to Hebrew.

  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. This may be problematic for some users because a formula such as =YEAR("1/1/25") returned 1925 in earlier versions of Excel, but in Excel 97 the same formula returns 2025. Because this only happens when "1/1/25" is a string using a 2-digit-year format, a solution is to change the "yy" date strings to "yyyy" date strings. The Date Migration Wizard, an Excel add-in tool, can also help the user identify and correct these situations.

Two-digit shortcut handling:

See the preceding discussion. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029. For more information, see Knowledge Base (KB) article Q164406.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel parses the date to January 1, 2015. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. For more information, see KB article Q180159.
  • The DATE() function is not designed to take 2-digit year shortcuts since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if the user were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015. The user cannot pass the DATE()function Hebrew year, month and day. Even if the cell is formatted with B2 prefix, Hebrew Excel 97 will take calculate the Gregorian date based on the parameters passed to it and then will convert the date to Lunar Calendar.
  • Recording date entry in a macro records/plays back the year in YY format even if the user enters YYYY and even if the system short date format was YYYY. For example if the system date was MM/dd/yyyy and the user enters in a cell 12/12/2030, Hebrew Excel 97 will play it back as 12/12/1930. This may cause problems if the two-digit year is not meant to follow the 1930-2029 date window that is mentioned above. See Knowledge Base article Q180159 for more information.
  • Since Visual Basic for Applications macro recorder uses English settings only and not Regional Settings and since Hebrew Excel parses Hebrew Lunar Calendar dates based on custom format and not based on the system calendar, it is not possible to have the recorder record a Hebrew date entry.
  • Using a format such as "Dec 98" or "12/98" will not function properly at the year 2001. Because 98 is too large to be a day of the month, Excel assumes it is a year. However, Excel assumes "Dec 01" is December 1 of the current year. Because Excel always stores the complete date, users can avoid ambiguity by entering a full date, regardless of the display formatting. For more information, see KB article Q180952.
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015.
  • Due to the ambiguous nature of text dates, in general they will always have some potential for error. Whenever possible, use serial dates and take great care when transferring text dates.
  • When dates must be transferred between programs, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as February 1, 1925; January 2, 1925; February 1, 2025; or January 2, 2025. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit-year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date.
  • For Hebrew Excel 97 users and in order to avoid confusion or miscalculations, users should stick with one type of date representation on the same sheet. If a user decides to Hebrew, they should stick with Hebrew dates.
  • Hebrew Excel 97 will not display in a worksheet cell the date for the 1st of January for the first leap year following a non-leap century year. Enter "1-Jan-2104"… the cell will display "1-Feb-2104". Note that 2100 is a century year, but not a leap year, and 2104 is the first leap year following. Though the date appears wrong in the cell, the serial value stored in memory is correct and calculations based on the date should be accurate. See KB article Q175362 for more information.

 

Microsoft has created the following add-in tools to help users identify Year 2000 issues and solutions in Excel 97 and later versions:

  • The Date Migration Wizard is designed to help users find instances where date-related arguments reference text dates that only specify the last 2 digits of a year--which can cause changes in calculation from earlier versions of Excel.
  • The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change all date formats in a workbook to formats that display all 4 digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks.
  • The Date Watch Wizard runs in the background while users work in Excel. It suggests alternatives when ambiguous text dates are entered in cells or functions, changes number formats to 4-digit years when 2-digit years are entered, and displays an alert when text files that contain 2-digit years are opened.

For more information about these add-in tools, see KB article Q176943.

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with nonduplicated production files because side effects with other noncompliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The following table can be used to guide testing of Excel within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as TXT, DIF, CSV, PRN.
The default column width with default fonts may truncate characters with date formats that have eight digits and two separators. To correct this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources

Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from previous versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions

Date entry

Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Because chart labels are normally used for display and not for calculation, they may not be much of an issue.

Visual Basic/Visual Basic for Applications (VB/VBA)

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to the wrong century. This may also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Excel has been designed for calculations in the year 2000 and beyond. Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit-year format.

To change the system short date format, do the following. On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

  • Test 1--Verify that Hebrew Excel transitions smoothly into the year 2000:

    Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired, it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 P.M., December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 1 minute, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test. Repeat the test with the Lunar equivalent date and with Calendar set to Lunar in Control Panel/Regional Settings.

 

  • Test 2--Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes 2000 as a leap year.

Note: The year 1900 is not a leap year; however, in your testing you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by 4, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. For more information, see KB article Q181370.

  • Test 3-- Verify that Hebrew Excel 97 parses dates before Jan 1, 1900 to Lunar.

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.

 

 

 

 

 

 

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Hungarian)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Hungarian OS: 32-Bit Win Release Date: N/A
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Italian)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Italian OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Japanese)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Japanese OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2 or the year 2000 software update in Office 97
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with Service Pack 5 or greater, or Windows NT 4 with Service Pack 4 or greater.
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 and Office 97 year 2000 software update as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: For Excel 97 to achieve compliant status, the Office 97 Service Release 2 (SR-2) patch must be downloaded from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR-2, including year 2000 updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All year 2000 issues reported as fixed in SR-2 exist in SR-1 and in the base Office 97 product.

Note: to install Office 97 SR-2, Office 97 SR-1 is required. Microsoft has prepared a year 2000 software update only for customers who have not installed Office 97 SR-1.

You can download this software update from the following site:

http://www.microsoft.com/japan/office/OfficeFreeStuff/Office/O97y2k/default.htm

This update software is the same as the year 2000 software update in Office 97

SR-2.

Special Note for East Asian versions of Excel:

  • East Asian versions of Excel 97 SR-2 includes a new method for parsing Gregorian dates. The new behavior is optimized to be the easiest way to deal with 21st century dates. In addition, East Asian versions of Excel 97 SR-2 also contain the old method for parsing Gregorian dates.
  • The default setting for Japanese Excel 97 SR-2 is the old method for parsing Gregorian dates.
  • To switch between the two date parsing behaviors, look on the SR-2 CD under \Valupack\XLParse for two files: "Newparse.reg" and "Oldparse.reg". Double clicking the file sets a registry key so that the next time that Excel starts up, it is in the desired date parsing mode.
  • In this compliance document, any reference tagged with (OLD DATE PARSING MODE ONLY) applies both to Excel 97 SR-2 in the old parsing mode, and also to Excel 97 SR-1 and earlier versions of Excel 97. References not tagged with (OLD DATE PARSING MODE ONLY) can be assumed to apply to the new date parsing mode in SR-2.

How the product handles dates:

  • Storage. Microsoft Excel stores dates as numeric values, with day #1 being 1900/1/1. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. Visual Basic/Visual Basic for Applications uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue with Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.
  • Formatting. When Microsoft Excel formats a date, it uses one of several default formats. If the system short date is a YY format, when the user types a YY date (a 2-digit year ), it will by default display in a YYYY (4-digit year) format.
  • Parsing on date entry. If a user enters a date in a "yy-m-d" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "25-1-1" used to parse to 01-JAN-1925, but with SR2 now parses to 01-JAN-2025. To avoid ambiguity display dates in a YYYY (four-digit year) format so the century is clearly shown.
  • (OLD DATE PARSING MODE ONLY). If a user enters a date in a "yy/mm/dd" format, it will be interpreted as a Japanese era date. For instance, "1/2/3" will parse to 03 FEB 1989, or February 3, Heisei year 1. To avoid ambiguity, enter dates in a YYYY/MM/DD format so they can be clearly understood as Gregorian dates. Or enter dates with a prefix for the Japanese era, such as H, S, T, or M, so they can be understood as a Japanese era date.
  • (OLD DATE PARSING MODE ONLY). On a default Japanese system, if a user enters a 21st century date in a "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, enter dates in a YYYY/MM/DD format so the date can be clearly understood.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. The Date Migration Wizard, an Excel add-in, will be available shortly to aid the user in identifying and correcting these situations. See below for more information.

Two-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

  • If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, the user has the date January 1, 1915. The user copies the date, but the system settings are "M/d/yy", and the text that is copied is "1-1-15". When "1-1-15" is then pasted into Microsoft Excel, it will parse the date to January 1, 2015. Such a change can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See Knowledge Base article Q180159 for more information.)
  • The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) were entered, the resulting date would be January 1, 1915, not 2015.
  • Using a format such as "Dec 98" or "12/98" will not function correctly at the year 2001. This is because 98 is too large to be the day of month so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year, as 01 is small enough to be interpreted as a day of the month. (See Knowledge Base article Q180952 for more information.)
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Due to the ambiguous nature of text dates, in general they will have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.
  • Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.
  • Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2Y format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned potential problems.

Microsoft has creating an add-in tool to help users identify Year 2000 issues in solutions created in Microsoft Excel97:

  • The East Asian Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information go to http://www.microsoft.com/japan/Office/OfficeFreeStuff/Excel/xl97DateMig1/

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-system

Component

File

Various File Formats

  • Avoid storing 2-digit dates in text file formats such as TXT, DIF, CSV, and PRN.
  • The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To resolve, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources

Sort

  • Data imported from databases and other external sources is often imported as text. Importing 2-digit dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel so use 4-digit dates to prevent confusion.

Basic Use

Functions

Date Entry

Natural Language Functions

  • Functions referring to text dates will parse according to the 2029/1930 cutoff rule.
  • Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

  • Since chart labels are normally used for display, and not for calculation, this shouldn't pose much of an issue.

Visual Basic /Visual Basic for Applications

Transfer between Visual Basic /Visual Basic for Applications and cells

  • Internally, Visual Basic for Applications treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the test recommendations below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

  • Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If users decide not to set the system short date format to include a 4-digit year, each cell can be formatted individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".
  • Verify that Microsoft Excel transitions into the year 2000: Warning! Before conducting this test, make sure there is no software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network so it is highly recommended that the computer be isolated from other systems before changing the system clock to conduct the following test.
  • Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset the system clock to the correct time and date after conducting this test.
  • Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, while testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See Knowledge Base article Q181370 for more information.)

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Korean)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Korean OS: 32-Bit Win Release Date: 01 Apr 1997
Operational Range: 01 Jan 1900 - 31 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98 or Windows NT 3.51 with Service Pack 5 or greater, or Windows NT 4 (no specific Service Pack is required, though Service Pack 4 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Office 97 Service Release 2 (SR-2) is required for Year 2000 compliance. SR-2 can be downloaded from http://www.microsoft.com/korea/office/97/sr2.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Notes for East Asian versions of Excel

  • East Asian versions of Excel 97 Service Release-2 (SR-2) include a new method for parsing Gregorian dates. The new behavior is optimized to be the easiest way to deal with dates in the 2000s. East Asian versions of Excel 97 SR-2 also contain the old method for parsing Gregorian dates.
  • The default setting for Korean Excel 97 SR-2 is the new method for parsing Gregorian dates.
  • To switch between the two date-parsing behaviors, look on the SR-2 CD under \Valupack\XLParse for the following two files: "Newparse.reg" and "Oldparse.reg." Double clicking a file sets a registry key so that the next time Excel starts up, it is in the desired date-parsing mode.
  • In this document, any reference tagged with (Old Date-Parsing Mode) applies both to Excel 97 SR-2 in the old parsing mode and to Excel 97 SR-1 and earlier versions of Excel 97. References not tagged with (Old Date-Parsing Mode) apply to the new date-parsing mode found in SR-2.

How the product handles dates:

  • Storage. Excel stores dates as numeric values, with day 1 being 1900/01/01. Excel 97 recognizes 1900/01/01 through 9999/12/31 as valid dates. Visual Basic (VB) and Visual Basic for Applications (VBA) use the same serial date system, with the exception of 1900/01/01 through 1900/02/28, where the values are different by 1. This difference is a result of a backward-compatibility issue with Lotus 1-2-3, which treats 1900 as a leap year. Previous versions of Excel recognize 1900/01/01 through 2078/12/31 as valid dates.
  • Formatting. When Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a "yy" format ("yy" refers to a 2-digit year), then even when the user types a 4-digit-year (yyyy) date, it will by default display in a 2-digit-year (yy) format. The date format is customizable. For customers requiring the highest level of assurance concerning the reliability of their date data, it is recommended that users change the system short date to a "yyyy" format.
  • Parsing on date entry. (Old Date-Parsing Mode) If a user enters a date in a "yy-m-d" or "yy/mm/dd" format, it will parse to a 1900 date, except for the year "00" which parses to 2000. To avoid ambiguity, dates should be entered in a "yyyy-m-d" or "yyyy/m/d" format. With the new date-parsing mode, the default setting is for 0 to 29 to parse as 20xx, and 30 to 99 to parse as 19xx.

    (Old Date-Parsing Mode) On a default Korean system, if a user enters a date in an "mm/dd/yy" format, some cases will be interpreted as a "yy/mm/dd" format. To avoid ambiguity, dates should be entered in a "yyyy/mm/dd" format so that the date can be clearly understood.
  • String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry described above. Users need to be aware that a formula such as =YEAR("25/1/1") which returned 1925 in earlier versions, will now return 2025 with the new date-parsing mode. Note that this happens only when "25/1/1" is a string using a 2-digit year format. The East Asian Date Migration Wizard, discussed under "Common date usage errors," can help the user identify and correct these situations.

Two-digit shortcut handling:

See the preceding discussion. With the old parsing mode, conversion of 2-digit shortcut dates assumes that 2-digit years are in the 1900s. The year "00" parses to 2000.

Common date usage errors:

  • If a date is pasted from one program to another using only the last 2 digits of the year, Excel might parse the date differently than the originating program. Example: The date January 1, 1915, is in a non-Excel program. The date is copied, but because the system settings are "M/d/yy," all that is copied is the text "1/1/15." When "1/1/15" is pasted into Excel, Excel parses the date to January 1, 2015. Such an error can also occur when one program is using an "M/d/yy" format while another is using a "d/M/yy" format. This also applies to importing dates from text files. For more information, see Knowledge Base (KB) article Q180159.
  • Because it receives numeric parameters, the DATE() function is not designed to take 2-digit-year shortcuts. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if a formula such as =DATE(15,1,1) is entered, the resulting date is January 1, 1915, not 2015. Dates in 20xx result by increasing the offset number.
  • Recording date entry in a macro only records the year according to the system short date format, which results in parsing a 2-digit year in playback. For more information, see KB article Q180159.
  • Using a format such as "Dec 98" or "12/98" will not function properly at the year 2001. Because 98 is too large to be a day of the month, Excel assumes it is a year. However, Excel assumes "Dec 01" is December 1 of the current year. For more information, see KB article Q180952.
  • An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.
  • Due to the ambiguous nature of text dates, in general they will always have some potential for error. Whenever possible, use serial dates and take great care when transferring text dates.
  • When dates must be transferred between programs, ideally they should be transferred as serial dates. They should never be transferred as an ambiguous text format that doesn’t specify the century and causes confusion between the month and the day of the month. For example, the text "2/1/25" could be interpreted as February 1, 1925; January 2, 1925; February 1, 2025; or January 2, 2025. Changing the default system short date format to include a 4-digit year and getting in the habit of using 4-digit-year formats will make the date visible if a user mistakenly enters a date in the wrong century.
  • Defined names store references only as text strings. Because they do not store dates as serial values, they are vulnerable to century issues when a "yy" format is used. Using defined names in this way is also problematic because users who use a date format with an order other than M-d-y will experience miscalculations. Both of these potential problems can be avoided by defining the name that refers to a cell containing a serial date.

Microsoft is creating the following add-in tool to help users identify Year 2000 issues in solutions created in Excel 97:

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because side effects with other non-compliant products cannot be predicted. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The following table can be used to guide testing of Excel within your organization.

Subsystem

Component

Testing notes

File

Various file formats

Avoid storing "yy" dates in text file formats such as TXT, DIF, CSV, or PRN.
The default column width with default fonts may truncate characters with date formats that have eight digits and two separators. To correct this, increase the column width or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, databases, external data sources

Sort

Data imported from databases and other external sources is often imported as text. Imported "yy" dates will be parsed with the 1930-2029 cutoff rule. Because this is different from later versions of Excel, use "yyyy" dates to prevent confusion.

Basic Use

Functions

Date entry

Natural language functions

Functions referring to text dates will parse according to the 1930-2029 cutoff rule.
Date entry will parse according to the 1930-2029 cutoff rule.

Visual Data

Charts

Chart labels are normally used for display and not for calculation.

Visual Basic/Visual Basic for Applications (VB/VBA)

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel does. However, VBA uses the "M/d/yy" format, so users should avoid transferring the date text through VBA because it could parse to the wrong century. This may also help avoid issues with international users who have a system short date format with an order other than M-d-y.

Additional Testing Instructions

Microsoft understands that, for various reasons, customers may be required to conduct their own Year 2000 certification testing. The following tests may aid customers in their own certification of Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Custom on the Number tab (Format menu, Cells command) in Excel, and then entering a 4-digit-year format.

To change the system short date format, do the following. On the Windows Start menu, point to Settings, click Control Panel, double-click the Regional Settings icon, and then click the Date tab. In the Short date style list, click a format that includes a 4-digit year ("yyyy").

  • Test 1--Verify that Excel transitions smoothly into the year 2000:

    Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired, it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 P.M., December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After 1 minute, press the F9 key to recalculate the formula that you entered in A1. Note that the time and date shown are in the year 2000 and that nothing unusual has happened to Excel. Remember to reset your system clock to the correct time and date after conducting this test.

  • Test 2--Verify that Excel recognizes the year 2000 as a leap year:

    Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, which indicates that Excel correctly recognizes 2000 as a leap year.

Note: The year 1900 is not a leap year; however, in your testing you may notice that Excel treats 1900 as if it is. This algorithm is by design and was adopted to maintain compatibility with dates in Lotus 1-2-3. The calculation for leap years that is used by the Gregorian calendar is as follows: If a year is evenly divisible by 4, it is a leap year unless it is also evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year unless it is also evenly divisible by 400. For more information, see KB article Q181370.

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.

 


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Microsoft Year 2000 Resource Center
Excel 97  8.0   (Norwegian)

Product Summary
Product: Excel 97 Version: 8.0 Category:Compliant*
Language: Norwegian OS: 32-Bit Win Release Date: 01 Nov 1996
Operational Range: 01 Jan 1900 - 13 Dec 9999
Prerequisites: Office 97 Service Release 2
Product Dependencies: Windows 95, Windows 98, or Windows NT 3.51 with SP 5 or greater, or Windows NT 4 (no specific SP is required, though SP 2 is recommended)
Clock Dependencies: System clock
Last Updated: 15 Nov 1999
Product Details

Product Maintenance: While Microsoft continues to recommend that customers install the most current Service Pack/Release for non-Year 2000 reasons, we understand that, for many reasons, this may not be possible. In order to aid our customers' Year 2000 efforts, Microsoft intends to maintain Office 97 Service Release 2 as compliant through January 1, 2001. Newer Service Packs are also to be maintained as compliant, and may include additional non-Year 2000 updates. This is intended to minimize the Year 2000 as a reason to upgrade.

Prerequisites: Download the Office 97 SR2 Patch from http://officeupdate.microsoft.com/Articles/sr2fact.htm. The changes in Office 97 that were made in SR 2, including Y2K updates, are listed in http://support.microsoft.com/support/kb/articles/q151/0/20.asp. All Y2K issues reported as fixed in SR2 exist in SR1 and in the base Office 97 product.

Description of how the product handles dates:

Storage. Microsoft Excel stores dates as numeric values, with day #1 being 01/01/1900. Excel 97 recognizes 01-JAN-1900 through 31-DEC-9999 as valid dates. VB/VBA uses the same serial date system, with the exception of 1-JAN-1900 through 28-FEB-1900, where the values are different by 1, as a result of a backward-compatibility issue for a bug in Lotus 1-2-3 that treats 1900 as a leap year. Previous versions of Excel recognize 01-JAN-1900 through 31-DEC-2078 as valid dates.

Formatting. When Microsoft Excel formats a date, it uses one of several default formats. The most common is the system short date. If the system short date is a YY format, then even when the user types a YYYY date, it will by default display in a YY format. To avoid this, the default format can be changed to a YYYY format.

Parsing on date entry. If a user enters a date in a "M/d/yy" format, less than 30 is 20XX, and equal to or greater than 30 is 19XX. So, for instance, "1/1/25" used to parse to 01-JAN-1925, but now parses to 01-JAN-2025. Suggest displaying dates in a YYYY format so the century is clearly shown.

String date parsing during calculations. If a formula takes a string date as an argument, the string date is currently parsed using the same code as the date entry shown above. This may be a concern to some users because a formula such as =YEAR("1/1/25") returned 1925 in previous versions, but in Excel97 returns 2025. Note that this only happens when "1/1/25" is a string using a 2-digit year format. Also, the Date Migration Wizard, an Excel add-in, is available to aid the user in identifying and correcting these situations. See below for more information and a link to the Date Migration Wizard.

 

2-digit shortcut handling:

See discussion above. Conversion of 2-digit shortcut dates assumes a date window of 1930 through 2029.

Common date usage errors:

If a date is pasted from one application to another using only the last two digits of the year, Microsoft Excel might parse the date differently than the originating application calculated it. Example: In a non-Excel application, you have the date January 1, 1915. You copy the date, but your system settings are "M/d/yy", and all that is copied is the text "1/1/15". When you paste "1/1/15" into Microsoft Excel, it will parse the date to January 1, 2015. Such an interpretation can also occur when one application is using a "M/d/yy" format while another application is using a "d/M/yy" format. This also applies to importing dates from text files. (See KB articles Q180159 for more information.)

The DATE() function is not designed to take 2-digit year shortcuts, since it receives numeric parameters. The DATE() function calculates a number less than 1900 as an offset from 1900. So, if you were to enter a formula such as =DATE(15,1,1), the resulting date would be January 1, 1915, not 2015.

Using a format such as "Dec 98" or "12/98" will not function correctly in the year 2001. This is because 98 is too large to be the day of month, so Microsoft Excel assumes it is a year. However, Microsoft Excel assumes "Dec 01" refers to December 1 of the current year. Since Microsoft Excel always stores the complete date, you can avoid ambiguity by entering a full date regardless of the display formatting. (See KB article Q180952 for more information.)

An undocumented behavior of Microsoft Query (all versions) may unintentionally encourage some users to enter a date criterion by specifying merely a month and day (such as "12/25"). In that instance, Query interprets the date as month and day of the current year. When the current year is equal to or greater than 2000, a malformed SQL statement is generated. In the event that this occurs, an error is generated and no data is returned. Avoiding this error is readily accomplished by entering a full and complete date. Microsoft recommends that all dates be entered in unambiguous formats, including a 4-digit year, but current versions of Microsoft Query also support windowing of 2-digit year dates as described in the Excel Year 2000 Product Guides.

Due to the ambiguous nature of text dates, in general they will always have some potential for error. Use serial dates whenever possible and take great care when transferring text dates.

Change the default system short date format to include a 4-digit year. Get in the habit of using 4-digit year formats for dates in Microsoft Excel. Such a practice will make the date visible if a user mistakenly enters a date in the wrong century. When dates must be transferred between applications, ideally they should be transferred as serial dates. They should not be transferred as an ambiguous text format that doesn't specify the century and causes confusion between month and day-of-month. For example, the text "2/1/25" could be interpreted as Feb. 1, 1925, Jan. 2, 1925, Feb. 1, 2025, or Jan. 2, 2025.

Defined names store references only as text strings. Since they do not store dates as serial values, they are vulnerable to century issues when a 2-digit year format is used. Using defined names in this way is also or concern because users who use a date format with an order other than M-d-y will experience interpretive miscalculations. Recommended usage is to define the name referring to a cell containing a serial date, which will avoid both of the above-mentioned concerns.

 

Microsoft has created three add-in tools to help users identify Year 2000 issues in solutions created with Microsoft Excel97:

The Date Migration Wizard is designed to help users find instances where date-related arguments are referencing text dates that only specify the last two digits of a year. This can cause changes in calculation from previous versions of Microsoft Excel. For more information see Knowledge Base article Q176943.

The Date Fix Wizard helps users find errors where the wrong century was entered for a date. It also allows the user to change date formats in a workbook to formats that display four digits of the year. Finally, it allows the user to scan workbooks for the earliest and latest dates in workbooks. For more information see Knowledge Base article Q176943.

The Date Watch Wizard runs in the background while you are working in Excel. The Date Watch Wizard will suggest alternatives when you enter ambiguous text dates in cells or functions, change number formats to four-digit years when you type two-digit years, and display an alert when you open text files that contain two-digit years. For more information see Knowledge Base article Q176943.

 

Testing guidelines and recommendations:

In general, avoid testing in a production environment or with non-duplicated production files because one cannot predict side effects with other non-compliant products. Interoperability testing with other Microsoft Office products can be conducted safely.

The following areas should be examined to verify whether dates are being properly used. The table below can be used to guide testing of Microsoft Excel within your organization.

Sub-System

Component

 

File

Various File Formats

Avoid storing 2Y dates in text file formats such as TXT, DIF, CSV, PRN. The default column width with default fonts may truncate characters with date formats that have 8 digits and two separators. To correct, increase the column width, or change the font to a fixed-width typeface such as Courier New.

Data

Import from: text, Databases, External data sources Sort

Data imported from databases and other external sources is often imported as text. Importing 2Y dates will be parsed with the 2029/1930 cutoff. This is different from previous versions of Excel, so use 4Y dates to prevent confusion.

Basic Use

Functions Date Entry Natural Language Functions

Functions referring to text dates will parse according to the 2029/1930 cutoff rule. Date entry will parse according to the 2029/1930 cutoff rule.

Visual Data

Charts

Since chart labels are normally used for display, and not for calculation, this should not pose a significant issue.

VB/VBA

Transfer between VB/VBA and cells

Internally, VBA treats dates as serial values, exactly like Excel. However, since VBA uses the "M/d/yy" format, you should avoid transferring the date text through VBA, since it could parse to the wrong century. This will also help avoid issues with international users who have a system short date format with an order other than M-d-y.

 

Additional Testing Instructions

Microsoft Excel has been designed for calculations in the year 2000. Microsoft understands that for various reasons customers may be required to conduct their own year 2000 certification testing. Microsoft provides the tests below to aid customers in conducting their own year 2000 certification of Microsoft Excel.

Excel is designed to handle 2-digit year shortcuts well into the next century. Dates are stored internally, in a complete form, with full century information. Nevertheless, a user or administrator may elect to change the operating system short date format to a 4-digit display in order to avoid ambiguity when reading or transferring dates. Note that this change can affect column widths and print layout and it could require additional changes in your worksheets. If you decide not to set your system short date format to include a 4-digit year, you can format each cell individually by selecting Format/Cells/Number/Custom, and entering a 4-digit year format. To change the system short date format, press the Start button, then select Settings, Control Panel, Regional Settings, select the Date page, then change the Short Date Style to a format that includes a 4-digit year by replacing the "yy" portion with "yyyy".

Verify that Microsoft Excel transitions smoothly into the year 2000:Caution! Before conducting this test, make sure you do not have any software containing a license that expires by the year 2000. This is especially common with beta copies of software programs. If a program determines that its license has expired it is possible the program will no longer boot, even after resetting the system clock. Changing a system clock on a network can affect other computers connected to the network, so it is highly recommended that you isolate the computer from all other systems before changing the system clock to conduct the following test.

Set the system clock to 11:59 p.m. December 31, 1999. Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter =NOW(). After one minute, press {F9} to recalculate the formula you entered in A1. Note that the time and date shown will be in the year 2000, and nothing unusual has happened to Microsoft Excel. Remember to reset your system clock to the correct time and date after conducting this test.

Verify that Microsoft Excel recognizes the year 2000 as a leap year: Start Excel. In cell A1 (cell R1C1 if in R1C1 mode), enter "=DATE(2000,2,28)+1". Note that the resulting date is February 29, indicating that Excel correctly recognizes that 2000 is a leap year.

Note: The year 1900 is not a leap year. However, in your testing you may notice Microsoft Excel treats 1900 as a leap year. This algorithm was adopted to maintain compatibility with dates in Lotus 1-2-3, and is by design. The calculation for leap years used by the Gregorian calendar is as follows. If a year is evenly divisible by four, it is a leap year, unless the year is evenly divisible by 100. If a year is evenly divisible by 100, it is not a leap year, unless it is also evenly divisible by 400. (See KB article Q181370 for more information).

Excel 97 uses a number of Microsoft Office 97 shared files for the implementation of dialogs and toolbars, task automation, online help, installation, graphics, file find and file I/O. For additional information that is appropriate for Excel 97, please refer either to the document for the particular Office version that this application came with, or, in the case of a standalone product, to any version 97 Microsoft Office document.


Legend of Symbols:
*The product is compliant. User action is recommended, which may include loading a software update or assessing shared technology.
#The product is compliant with an acceptable deviation from Microsoft's standard of compliance. An acceptable deviation does not affect the core functionality, data integrity, stability or reliability of the product.
+The product is compliant . Software updates are pending. Future maintenance actions will be recommended shortly.
Note: Compliance ratings given for each product assume that all recommended actions have been taken.


Itemized List of products in each Volume

YEAR 2000 READINESS DISCLOSURE

ALL COMMUNICATIONS OR CONVEYANCES OF INFORMATION TO YOU CONCERNING MICROSOFT AND THE YEAR 2000, INCLUDING BUT NOT LIMITED TO THIS DOCUMENT OR ANY OTHER PAST, PRESENT OR FUTURE INFORMATION REGARDING YEAR 2000 TESTING, ASSESSMENTS, READINESS, TIME TABLES, OBJECTIVES, OR OTHER (COLLECTIVELY THE "MICROSOFT YEAR 2000 STATEMENT"), ARE PROVIDED AS A "YEAR 2000 READINESS DISCLOSURE" (AS DEFINED BY THE YEAR 2000 INFORMATION AND READINESS DISCLOSURE ACT) AND CAN BE FOUND AT MICROSOFT'S YEAR 2000 WEBSITE LOCATED AT http://microsoft.com/year2000/ (the "Y2K WEBSITE"). EACH MICROSOFT YEAR 2000 STATEMENT IS PROVIDED PURSUANT TO THE TERMS HEREOF, THE TERMS OF THE Y2K WEBSITE, AND THE YEAR 2000 INFORMATION AND READINESS DISCLOSURE ACT FOR THE SOLE PURPOSE OF ASSISTING THE PLANNING FOR THE TRANSITION TO THE YEAR 2000. EACH MICROSOFT YEAR 2000 STATEMENT CONTAINS INFORMATION CURRENTLY AVAILABLE AND IS UPDATED REGULARLY AND SUBJECT TO CHANGE. MICROSOFT THEREFORE RECOMMENDS THAT YOU CHECK THE Y2K WEBSITE REGULARLY FOR ANY CHANGES TO ANY MICROSOFT YEAR 2000 STATEMENT. EACH MICROSOFT YEAR 2000 STATEMENT IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. CONSEQUENTLY, MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. MOREOVER, MICROSOFT DOES NOT WARRANT OR MAKE ANY REPRESENTATIONS REGARDING THE USE OR THE RESULTS OF THE USE OF ANY MICROSOFT YEAR 2000 STATEMENT IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY, OR OTHERWISE. NO ORAL OR WRITTEN INFORMATION OR ADVICE GIVEN BY MICROSOFT OR ITS AUTHORIZED REPRESENTATIVES SHALL CREATE A WARRANTY OR IN ANY WAY DECREASE THE SCOPE OF THIS WARRANTY DISCLAIMER. IN NO EVENT SHALL MICROSOFT OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER REGARDING ANY MICROSOFT YEAR 2000 STATEMENT INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS, PUNITIVE OR SPECIAL DAMAGES, EVEN IF MICROSOFT OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, SO THE FOREGOING LIMITATION MAY NOT APPLY TO YOU. THE INFORMATION CONTAINED IN EACH MICROSOFT YEAR 2000 STATEMENT IS FOUND AT THE Y2K WEBSITE AND IS INTENDED TO BE READ IN CONJUNCTION WITH OTHER INFORMATION LOCATED AT THE Y2K WEBSITE, INCLUDING BUT NOT LIMITED TO MICROSOFT'S YEAR 2000 COMPLIANCE STATEMENT, THE DESCRIPTION OF THE CATEGORIES OF COMPLIANCE INTO WHICH MICROSOFT HAS CLASSIFIED ITS PRODUCTS IN ITS YEAR 2000 PRODUCT GUIDE, AND THE MICROSOFT YEAR 2000 TEST CRITERIA.

ANY MICROSOFT YEAR 2000 STATEMENTS MADE TO YOU IN THE COURSE OF PROVIDING YEAR 2000 RELATED UPDATES, YEAR 2000 DIAGNOSTIC TOOLS, OR REMEDIATION SERVICES (IF ANY) ARE SUBJECT TO THE YEAR 2000 INFORMATION AND READINESS DISCLOSURE ACT (112 STAT. 2386). IN CASE OF A DISPUTE, THIS ACT MAY REDUCE YOUR LEGAL RIGHTS REGARDING THE USE OF ANY SUCH STATEMENTS, UNLESS OTHERWISE SPECIFIED BY YOUR CONTRACT OR TARIFF.

Wednesday, November 17, 1999
© 1999 Microsoft Corporation. All rights reserved. Terms of use.

This site is being designated as a Year 2000 Readiness Disclosure and the information contained herein is provided pursuant to the terms hereof and the Year 2000 Information and Readiness Disclosure Act.