I'm trying to count unique values based on muliple criteria. I tried using
the formula
=SUMPRODUCT(--(B2:B2500=B2),--(D2:D2500="HY")/COUNTIF(F2:F2500,F2:F2500)) but
when there's a blank in column "F" I get an error. Can this formula be writen
to ignore blank cells?

Thank you in advance for your help
Joe