Ok, I can't quite make this formulat work.
Assume: Column D is Birth Year, Column E is Death Year, Column F is Age at
Death

The basic formula is =E-D (Death Year minus birth year gives me age at death
(F))

What Im trying to do is if the death year column is blank (E), add 100 to
the birth year (D), then use that number as the E in the basic formula.
Similarly, if the birth year column (D) is blank, subtract 100 from the death
year (E) then use that as D in the =E-D formula.

This is the statement I've tried:
=IF(ISBLANK(E3), (E3=D3+100)), IF(ISBLANK(D3), (D3=E3-100)), E3-D3

Those "=" signs don't look right....I think that's part of it.
Help?! Thank you!!!!!

--
Rachel