Can I put a cell reference in a sumproduct formula

[soconfused]

I have the following formula and I would like to automate it a bit more. I
want to be able to have the month automatically pick up from another cell.

SUMPRODUCT(--(YEAR($L$5:$L$102)=2009),--(MONTH($L$5:$L$102)=2),$B$5:$B$102)

 

[Gary''s Student]

Like:

=SUMPRODUCT(--(YEAR($L$5:$L$102)=2009),--(MONTH($L$5:$L$102)=MONTH(Z100)),$B$5:$B$102)

 

[David Biddulph]

=SUMPRODUCT(--(YEAR($L$5:$L$102)=2009),--(MONTH($L$5:$L$102)=A2),$B$5:$B$102)
if your 2 for the month is in A2.