No. The conditional tests return arrays of TRUE/FALSE. The double unary
coerces these into arrays of 1/0. These 1/0 arrays are PRODUCTed and SUMmed
as per a normal SUMPRODUCT formula, =SUMPRODUCT(array1, array2,..).

--
HTH

Bob

(there's no email, no snail mail, but somewhere should be gmail in my addy)

"J Sedoff" wrote in message
...
M Kan -
I've seen the SumProduct() function used a lot with the "--" (double
minus),
what does that do? When I have used it it seems to ignore any values that
occur within that array, is it just telling Excel to treat it as a
condition,
rather than useable values?

Thanks, Jim

"M Kan" wrote:
=SUMPRODUCT(--(MONTH($C$3:$C$46)=F3))