Effective with Office 2011, Excel’s preferences will now default to using the 1900 date system instead of the 1904 date system. From Excel 2008 to 2011, this change is as simple as unchecking one preference selection, however, all new workbooks will now use the different date system by default.
What is significant about 1900 and 1904?
That could be a chicken-and-egg discussion. Excel for Mac uses the 1904 date system and Excel for Windows uses . . .
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