There's a typo in that formula. It's testing for January.

For August, array entered** :

=AVERAGE(IF((MONTH(B4:B21)=8)*(ISNUMBER(B4:B21)),D 4:D21))

** array formulas need to be entered using the key combination of
CTRL,SHIFT,ENTER (not just ENTER)

--
Biff
Microsoft Excel MVP


"dec697" wrote in message
...
=AVERAGE(IF((MONTH(B4:B21)=1)*(ISNUMBER(B4:B21)),D 4:D21))

I used the above formula and it didn't work.