Maybe better illustrated using this example:

A1 = 1/31/2009

What date should be returned after adding 1 month to the date in cell A1?

There is no 2/31/2009 so what date should be returned?

--
Biff
Microsoft Excel MVP


"Rick Rothstein" wrote in message
...
Months are such a terrible unit to perform math with. As an example, if
you add 6 months to the date August 31, 2009, what date do you expect to
have returned to you?

--
Rick (MVP - Excel)


"Gene" wrote in message
...
Excel 2003: I have a "date" in a cell (eg: 6/16/09), and want to
calculate
the date which is 6 months from now?
The issue I'm having is that some months are 29, 30, 31 days.

The "date" call value may change and the "x" months period could also
change.

Hope this is clear.
THANKS!
Gene:)