This is an array formula that must be entered using ctrl+shift+enter at the
same time.

=AVERAGE(IF(M1:M3=37,L1:L3))
--
Don Guillett
Microsoft MVP Excel
SalesAid Software

"Rebekah" wrote in message
...
I have two columns of data, one of which I need to calculate an average of
but only if the data in the 2nd column is of a certain value.
I can't work out how to do this...
For instance, I need to calculate the average number of calls taken within
week 37.
My columns look similar to:
No. of calls Week no.
10 37
8 38
4 37 etc