I suspect you'll ultimately be happier if you use a Pivot Table, which
can show the mean values for all months simultaneously:

http://peltiertech.com/Excel/Pivots/pivotstart.htm

But for an individual month you could use (array-entered):

=AVERAGE(IF(A1:A100=1,C1:C100,""))


In article ,
"Daniel" wrote:

Hi,

I have a file with data and some months on, the months
are as numbers, e.g. jan =1 , feb =2, . I would like to
be able to calcule the mean values based on data in col
a by month in col c. It would be good if i could have
just one formula that looks at the records in col c and
if it is say 1, than looks at the value in col and then
returns the median ov all records where colc is 1, then I
could do the same for the other months.

Hope this makes sense,

Cheers

Daniel