Hi,

There is some problem in the criteria of your formula. The criteria has to
be a range of cells and not an equation such as what you have used
(Main!$C$2:$C$266=$C11). Also please ensure that the headers of the range
and criteria are the same.

--
Regards,

Ashish Mathur
Microsoft Excel MVP
www.ashishmathur.com

"Andrew" wrote in message
...
I am trying to reduce a large dataset of 266 individuals of 23 species
into
one that just includes the means of each species. Species names are text
entries in column C. There are some missing data points, so I could not
simply use:
=SUMIF(Main!$C$2:$C$266,$C11,Main!FF$2:FF$266)/COUNTIF(Main!$C$2:$C$266,$C11)
because the countif is not counting the exact cells going into the sum.

So my current approach is to use DAVERAGE. I am specifying the
worksheet(Database?), column, and criteria. The criteria compares text in
the 2 columns

Daverage(Main!1:65536,FF$2:FF$266,Main!$C$2:$C$266 =$C11)
however, I am getting a #VALUE error.
any help, thanks