You have to specify your range. In this example, I've specifed row 2 to 100
in the persprective column.

=SUMPRODUCT(--(A2:A100="January"),--(B2:B100=""))

HTH,
Paul


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"TDW" wrote in message
...
How can I calculate the number of blank cells in Column O based on
information in Column A? By counting the number of blank cells I can
figure
how many apps. I still need to receive but I would like to do this per
month
(the months are listed in Column A) Any ideas?