Hi all.

A B C
1 1 50 1,979
2 1 50 -
3 1 50 -
4 1 50 205
5 1 50 -
6 1 50 507
7 1 50 289
8 1 50 -
9 2 50 443
10 2 50 480
11 2 50 -
12 2 7035 1,421
13 2 7035 -
14 2 7080 589
15 3 7080 -
16 4 7110 631
17 5 7112 1,617
I want to sum all items where the criterias are "1" and " 50"
My formula=SUMPRODUCT(($A$1:$A$17=1)*($B$1:$B$17=50)* $C$1:$C$17
and the result turn to be =0
Why the result is "0" and not 2,980?

any help & comments please.
thanks