Not sure if this can be done??

I have a worksheet where a number of the rows are hidden and need to exclude
these from calculations performed using SUMPRODUCT, ie;

=SUMPRODUCT(--(A1:A2000=C1)*(B1:B2000=D1))

but only looking at rows that are not hidden.

Is there a relatively simple way of doing this? If not I will just create
another column to show an 'X' when the row is not to be counted and then
make the calculation:

=SUMPRODUCT(--(A1:A2000=C1)*(B1:B2000=D1)*(E1:E2000<"X"))

Thanks.