Use a Pivot Table. See:

http://peltiertech.com/Excel/Pivots/pivotstart.htm
--
Gary''s Student - gsnu200791


"JNAP101" wrote:

I am trying to develop a spreadsheet which call calculate all draws on a
specfic invoice as demostrated below:
A B
123456 10.00
123456 10.00
789414 50.00
569855 30.00
569855 30.00
What forumula would give the following result if the P.O. numbers in "A"
change?
123456 20.00
569855 60.00
789414 50.00
Any help would be appreciated. Thank you.