I was wondering if it was possible to use 2 criteria for a count if formula.
I want to count the number of numbers in a range that are above 0. I would
write that like:

=COUNTIF(Sheet1!D2:F65536,">0")

I also have the "color" coded by using a number in column B that corisponds
to the color ie, 1=yellow 2=green and 3=red. If I want to count the number
of yellow values in a range I would use the formula:

=COUNTIF(Sheet1!B2:B65536,1)

Is it possible to count all of the possitive yellow values in the range
D2:F65536?