Use Peo's suggestion. It works. I was over-complicating things!
D Dave Peterson Oct 15, 2007 #22 =sumproduct() likes to work with numbers. The -- stuff changes trues and falses to 1's and 0's. Bob Phillips explains =sumproduct() in much more detail here: http://www.xldynamic.com/source/xld.SUMPRODUCT.html And J.E. McGimpsey has some notes at: http://mcgimpsey.com/excel/formulae/doubleneg.html
=sumproduct() likes to work with numbers. The -- stuff changes trues and falses to 1's and 0's. Bob Phillips explains =sumproduct() in much more detail here: http://www.xldynamic.com/source/xld.SUMPRODUCT.html And J.E. McGimpsey has some notes at: http://mcgimpsey.com/excel/formulae/doubleneg.html