Hi google groups?

I have been searching online to find a way to make a count by two
criteria - year and Y/N. In all the searching it seems I have to do a
sumproduct, and wrote the formula below. When I do countifs for each
individual criteria, I get the actual number (e.g. =COUNTIF('Other
Worksheet'!$M$4:$M$2000,"Y"), but when I use the sumproduct formula, I
receive a #VALUE! error message. I've used the " " for the text.
What else could cause this error message?

=SUMPRODUCT(('Other Worksheet'!$K$4:$K$2000=1997)*('Other Worksheet'!$M
$4:$M$2000="Y"))

Thanks!