Sum of individual data in column A for each unique cell

Hi,

I am sure there must be a simple way to do this, but I cannot find a formula to suit. I have a spreadsheet that lists invoice numbers in Column A. Column I contains the cost of each item for that invoice. What I need is to get excel to automatically find the same invoice numbers in column A and add up a total using the costs in Column I. In my attached example I have manually done what I need the formula to do in column L. Is this possible? Or is there a better way of doing this?

Cheers,

Linda

In L2 cell

Formula:

=IF(COUNTIF(A:A,A2)=COUNTIF($A$2:A2,A2),SUMIF(A:A,A2,I:I),"")

Drag it down...

For your understanding

The below formula will get the sum of that particular invoice

Formula:

=SUMIF(A:A,A2,I:I)

The below formula will confirm whether it is last entry

Formula:

=COUNTIF(A:A,A2)=COUNTIF($A$2:A2,A2)

Mingled both formula's and shown in initial suggestion