I think that this is an easy question but I simply couldn't find the answer.

I have the following list in XL2003

Column1 Column 2
PAYMENTS 100
CREDIT 200
PAYMENTS 1000

I want to create a formula somewhere in Sheet1 that will produce me the
equivalent of the sum of Column 2 where Column1=PAYMENTS. In other wants the
SUM of PAYMENTS is 1100. How can I access this sum using a formula somewhere
in my worksheet.

Thanks
Michael