See these:

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


http://mcgimpsey.com/excel/formulae/doubleneg.html

Biff

"Chris Cowles" wrote in message
...
What's the meaning of the leading double subtraction signs in the criteria
and sum_range?
--
Chris Cowles
Gainesville, FL

"Duke Carey" wrote in message
...
Assuming your data starts in cell A2, and that the first set of test
values
is found in C2 and D2, use this formula

=SUMPRODUCT($A$2:$A$11,--($B$2:$B$11C2),--($B$2:$B$11<D2))