In Microsoft Excel, you can use either of following two date systems.
Date system First day is Default date system in
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1900 Date System January 1, 1900 Microsoft Excel for Windows
Microsoft Excel for Windows NT
1904 Date System January 1, 1904 Microsoft Excel for the Macintosh
To change the date system for the active workbook, follow these steps:
- On the Tools menu, click Options or Preferences. Click the Calculation
tab.
- Click to select the 1904 Date System check box to use that date system;
to use the 1900 Date System, clear the check box.
- Click OK.
When you use the DATE function to return the serial number of a particular
date, and you use a one- or two-digit year argument, the function assumes
that the date is in the 20th century (19xx). Because the 1904 Date System
does not support dates before January 1, 1904, the DATE function fails if
you specify a year argument that is less than 1904. For example, the
following results are displayed.
Result when using Result when using
Formula 1900 Date System 1904 Date System
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=DATE(0,1,1) 1/1/1900 #NUM!
=DATE(1,7,5) 7/5/1901 #NUM!
=DATE(1902,8,12) 8/12/1902 #NUM! (since year < 1904)
=DATE(4,3,31) 3/31/1904 3/31/1904