conditional formula question with multiple criteria

[joe@malvern]

I need to sum the rows in a column that meet certain criteria.
column A= date
column B= has $ values
column c= has the dollar values I want to sum if the folling conditions are
met:

Column A date = January (01/01/09-01/31/09)
column B >"0"

resulting in sum of column c values

thanks!

 

[Luke M]

=SUMPRODUCT((MONTH(A2:A100)=1)*(B2:B100>0)*(C2:C100))
Note that range sizes must be equal, and you can't callout entire column
(unless using XL 2007)

If you need more exact dates, could use
=SUMPRODUCT((A2:A100>=DATEVALUE("1/1/09")*(A2:A100<=DATEVALUE("1/31/09")*(B2:B100>0)*(C2:C100))

 

[joe@malvern]

formula does not give me an error, however it returned a value of $0 when it
should have been $42,000 (6 january rows).

here is the formula as I entered it...do you see my error? thanks again for
your help

=SUMPRODUCT((K3:K299>=DATEVALUE("01/01/09")*(K3:K299<=DATEVALUE("01/31/09")*(O3:O299>0)*(M3:M299))))