Seemingly blank cell, if you have a formula returning a blank it is not
empty so you might want to use

=IF($Q2<"",F2+90,"")

if you by any chance are using spaces

=IF(TRIM($Q2)<"",F2+90,"")

--
Regards,

Peo Sjoblom

(No private emails please)


" Pivot Table/Query" wrote
in message ...
I have a new spreadsheet that I need to calculate a due date (column X)
based
on the initial appointment date (column Q).(the next appointment would be
90
days after the initial appointment) I want it to ignore blank cells. I
have
used the following formula which calculates the info fine, but it adds 90
days to blank cells also and gives me 3/30/1900. Please help
=IF(NOT(ISBLANK($Q2)),F2+90,"")