Richard,

Take a look at http://www.xldynamic.com/source/xld.SUMPRODUCT.html. I hope
that will explain it all to you.

--
HTH

Bob Phillips

"Richard Buttrey" wrote in
message ...
On Mon, 10 Oct 2005 09:29:05 +0100, "Bob Phillips"
wrote:

=SUMPRODUCT(--(A2:A20="x123"),--(D2:D20=4),C2:C20-B2:B20)

but I get 23

Just an observation, but presumably it needs a constant of +1 adding
??

I keep seeing these double negative signs appearing in these types of
formulae. They certainly don't work without them, but what's the
reason Excel requires them?

Rgds
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Richard Buttrey
Grappenhall, Cheshire, UK
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