Try this array formula

Count unique items in data(text, values, Formulas)

=SUM(IF(LEN(data),1/COUNTIF(data,data)))


--
Regards Ron De Bruin
http://www.rondebruin.nl



"Bob" wrote in message ...
Ron,
Thanks for your suggestion. Unfortunately, there was no example (or
solution) that counts unique cells (within a database) containing text at the
URL you provided.
Do you know of any other sites I can try?
Thanks again.
Bob


"Ron de Bruin" wrote:

Start here
http://www.j-walk.com/ss/excel/tips/tip52.htm

--
Regards Ron De Bruin
http://www.rondebruin.nl



"Bob" wrote in message ...
I have a column (within a database) containing hundreds of Project Numbers
(e.g., P8763, PA3229, P1090.1, etc.), and the same Project Number can appear
more than once in the column. I need to count the number of unique Project
Numbers within that column, based on the criteria of another column. Is
there a way to do that using a combination of the DCOUNTA function and a
formula? Any help would be greatly appreciated.
Thanks.