I should have said:

In row 2 enter
=IF(A2=A1,"",SUMIF(A:A,"="&A2,B:B))

and copy it down.

--
Dianne

In ,
Dianne typed:
If your data starts in row 1, then the formula for C1 would be:
=SUMIF(A:A,"="&A1,B:B)

Then in subsequent rows, use:
=IF(A2=A1,"",SUMIF(A:A,"="&A2,B:B))


I've following information wanted to group by first
column and show the sum of quantities:

a b c
---- ----- ------
123 10.8 75 - sum(10.8+20.2+44)
123 20.2
123 44
124 2 58 - sum(2+11+45+0)
124 11
124 45
124 0