Counting Dates that fall within a certain month + another criteria

Please see attached.

What formula would I put in D5 that will count how many times, in the "data" worksheet, that the column header (D4) appears with a test date next to it that falls within that month?

I will be copying it down for the rest of the months into 2015, and across for all column headers in row 4.

Let me know if I need to clarify anything!

Thanks

Try...

D5, copied across and down:

=SUMPRODUCT(--(Data!$A$2:$A$482=Testing!D$4),--(Data!$B$2:$B$482-DAY(Data!$B$2:$B$482)+1=Testing!$A5))

Yes it works! Thank you

Now hopefully I can convert it to fit my real spreadsheet!

You're very welcome!