Can't get Sumproduct to work: Excel 2003

[Emma C]

Hi, I've read lots of the answers on here and my query should be easy but I
really can't make my formula work! I need to count all the 1s in a column
where they were previously 0s

Example:

May June
0 1
0 1
0 1
0 1
1 1

Expected result here would be 4

I have tried: =sumproduct(P6570="0")*(Q6:Q570="1") but I get a value
error. I have checked and none of the cells contains text. I believe that
excel will ignore cells with no data in so that shouldn't be the problem (I
have included extra rows at the bottom of the formula to allow for growing
data over months!)

Any help would be most welcome as my head hurts!!!!

 

[Gary''s Student]

=SUMPRODUCT((P6570=0)*(Q6:Q570=1))

 

[Emma C]

I am an idiot - you are a genius and I can now finish work.

Thank you very much indeed (am mildly embarrassed but still quite happy that
you've sorted this for me!)

 

[Gary''s Student]

You are very welcome!