I am currently using this formula.

=SUMPRODUCT(--($C$6:$C$148=2006),--($E$6:$E$148=5000),--($G$6:$G$148=A),--
($I$6:$I$148))

Although all values in all the columns are numeric, one column stores
alphabetical values, and the formula is not returning any value. is it
because arrays have to contain the same data type?

Thanks in advance