Microsoft KB Archive/98603

= Microsoft Knowledge Base =

Excel: MONTH Function Returns Different Result Than Expected
Last reviewed: September 12, 1996

Article ID: Q98603

The information in this article applies to:


 * Microsoft Excel for the Macintosh, versions 3.0 and 4.0
 * Microsoft Excel for Windows, versions 3.0, 4.0, and 4.0a

SUMMARY
In the Examples section of the MONTH function in the &quot;Function Reference,&quot; versions 3.0 and 4.0, the examples assume that you are using the 1900 date system. If you are not using the 1900 date system, these examples may appear to be incorrect.

Note: The default date system for Microsoft Excel for the Macintosh is the 1904 date system. In the &quot;Function Reference,&quot; the following example shows a result of 12:

MONTH(366) equals 12 However in Microsoft Excel, if the date system is set to 1904, MONTH(366) will equal 1.

MORE INFORMATION
To use to the 1900 date system, choose Calculation from the Options menu and clear the 1904 Date System check box (to use the 1904 date system, select the 1904 Date System check box), and choose OK.

By default, Microsoft Excel for the Macintosh begins counting dates from the number 0, which corresponds to January 1, 1904 (the 1904 date system). Microsoft Excel for Windows begins counting dates from the number 1, which corresponds to January 1, 1900 (1900 date system).

In the above example, 366 is a date serial number. In the 1900 date system, this date is December 31, 1900, so the MONTH function will return 12. In the 1904 date system, this date is January 1, 1905, and therefore the MONTH function will return a 1.

For more information on using dates and times in Microsoft Excel, query on the following words in the Microsoft Knowledge Base:

date and time and function and appnote