Excel allows you to choose which arbitrary date you use as the beginning point for date and time serial numbers. In the PC world, the default date is January 1, 1900. If you are working with Excel workbooks imported from the Macintosh environment, however, you will want to set the starting date to January 2, 1904-the default date used on the Mac.
To set which of these two dates is used, follow these steps:
- Display the Excel Options dialog box. (In Excel 2007 click the Office button and then click Excel Options. In Excel 2010 and Excel 2013, display the File tab of the ribbon and then click Options.)
- Click Advanced at the left of the dialog box.
- Scroll through the available options until you see the section titled When Calculating this Workbook. (See Figure 1.)
- The Use 1904 Date System check box controls which dating system is used by Excel. If the check box is not selected, then the January 1, 1900 starting date is used; if it is selected, then January 2, 1904 is used.
Figure 1. The advanced options of the Excel Options dialog box.