Aug 08 2020 07:37 AM
Aug 08 2020 08:05 AM
Excel only handles dates from January 1, 1900. If you enter for example 01/01/1899 in a cell, you will see that it is left-aligned, indicating that Excel sees it as text instead of as a valid date.
If you want to perform calculations with dates before that, you could write user-defined functions (UDFs) in VBA. VBA handles older dates without problems.
Also see pre-1900 dates