Don helped me with a formula I was struggling with, and the two he developed
work PERFECTLY:

=AVERAGE(IF('Quarter 1 Data'!$G$4:$G$500="Allen",'Quarter 1
Data'!$C$4:$C$500))

=AVERAGE(IF('Quarter 1 Data'!$F$4:$F$500="OP",'Quarter 1 Data'!$C$4:$C$500))

I have one additional question however, and I'll use the following as an
example to describe what I am looking for:

If there is no input data yet for Row C or Row G, I would understadably see:
#DIV/0! in the cell referencing the first formula above (which I do). I
realize that as soon as I input any data into Rows C or G, the #DIV/0! error
will be replaced with the actual numeric data generated by the formula. This
would also be true of the second formula in the absence of any data in Rows C
or F.

Is there any way of using an IF statement to keep the cells blank, until the
relevant data is input. It's probably more of a cosmetic issue, but I just
hate seeing that "Division" error sign (even if the only assoicated error is
the lack of data in the specific cells requiring data).

Thanks!

Dan