I kind of figured it out, but still need some help. The problem was that the
dates are both formatted mmm-yy (eg, Nov-08), but the dates on the first
sheet are all for the first of the month, and the dates on the second sheet
are dates all over the month.

Is there anyway to match it just by month and year and ignoring the day of
the month?

Thanks,

"Cam1234" wrote:

Hi All,

I'm using the following formula to return data in a sheet:

=SUMPRODUCT(--(Demand1!$A$1:$A$9731=$A21),(--Demand1!$B$1:$B$9731=G$19),(--Demand1!$D$1:$D$9731=$B$17),(Demand1!$C$1:$C$9731) )

In the sheet with the formula, I have part numbers down column A, dates
across rows (19 in this case), and another text qualifier in B17.

In sheet "Demand1" I have 4 columns - A has part numbers, B has dates, C has
quantity (the value I want returned), and D has the text qualifier.

My problem is that the formula sometimes works and sometimes doesn't - it is
very tempermental. I've tried matching all the formating, and still
sometimes it does not work.

Anyone have any ideas?

Thanks,