=AVERAGE(IF(('Evaluation Detail'!$D$7:$D$499=DATE(2008,9,1))
*('Evaluation Detail'!$D$7:$D$499<=DATE(2008,9,30))
*('Evaluation Detail'!$F$7:$F$499="Thaddeus Thomas")
*('Evaluation Detail'!$Q$7:$Q$499<0),'Evaluation Detail'!$Q$7:$Q$499,0))

You MUST array enter it, it won't work otherwise.

--
HTH

Bob

(there's no email, no snail mail, but somewhere should be gmail in my addy)

"LPS" wrote in message
...
My Excel 2000 workbook has two sheets, the first (Evaluation Detail)
contains
details about course evalutions per instructor. Column A is Course Name,
B
and C are Course Numbers, D is Course Date, E is Training Provider, F is
Instuctor Name, G thru P are evaluation scores and Q is Evaluation
Average.

On the second sheet (Evaluation Summary) I want to calculate the overall
course average per instructor, per month. I have written an AVERAGE
statement which calls an IF/AND statement (see below). It works but
returns
the same results for each instructor. When I manually calculate the
averages
per instructor per date,they are not the same. Can anyone advise as to
why
my function is not working. I tried making it an array function
(CTRL+SHIFT+ENTER) but it caused the results to return "0" (and I don't
really understand array functions - :( )!

=AVERAGE(IF(AND('Evaluation
Detail'!$D$7:$D$499=DATE(2008,9,1),'Evaluation
Detail'!$D$7:$D$499<=DATE(2008,9,30)),IF('Evaluati on
Detail'!$F$7:$F$499="Thaddeus Thomas",IF('Evaluation
Detail'!$Q$7:$Q$499<0,'Evaluation Detail'!$Q$7:$Q$499,0))))

I greatly appreciate any and all help.
--
LPS