I am trying to write a sumproduct formula to add 4 numbers off 4 different
worksheets within the same file. Here is my formula:

=SUMPRODUCT(--(Southwest!A10:A126=1186),--(Midwest!A10:A124=1186),--(West!A10:A120=1186),--(East!A10:A118=1186),(Southwest!C10:C126+Midwest!C10:C124+West!C10:C120+East!C10:C118))

All of the four worksheets have 1186 as a value, and I'm getting a #value#
error when I hit enter. Is it possible to have a sumproduct function using 4
different sheets, or does it have to be in the same sheet?