Gert-Jan wrote:
Hi Bob, this works great, thanks a lot!

I have done a lot with formulas, but I have never seen that -- in a
formula before. Removing one makes the ammount negative, removing
them both makes the result zero.


You can see a very good explanation at Debra Dalgleish's site:

http://www.xldynamic.com/source/xld.SUMPRODUCT.html


--
Hope I helped you.

Thanks in advance for your feedback.

Ciao

Franz Verga from Italy