Quote Originally Posted by swaatacba
Where within Micorsoft's help system does it provide such vital information?
It doesn't, nor does it explain how to use SUMPRODUCT in this way.

I tell this story often, but it is enlihtening I feel. I was in Redmond at Microsoft one year, and I met up with an Excel help technical writer. This guy had no idea that you could use SUMPRODUCT in this way, it was all news to him.