=SUMPRODUCT(--(A1:A10000=915),--(C1:C10000=1001),C1:C10000)

Change the row numbers to fit your data.


--
Regards,
Dave
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"Cheryl W" wrote:

I want to sum the data in column c if column a= 915 and column c =1001. I
can't get it to recognize the 2nd condition (column c=1001). Please help!