Hi, i have strange problem doing reporting:

i have numerous clients with different issued invoices. Problem comes to the point when there are invoices in minus and plus:

Column A consists of client unique IDs, Column B invoice number, column C invoice amount

A          | B          | C 

0010019991 | 1800149471 | 162.00 | 2010-03-12

0010019991 | 1800136388 | 162.00 | 2010-02-12

0010019991 | 1600008004 | -36.00 | 2010-03-15

0010021791 | 1800132148 | 162.00 | 2010-03-12

0010021791 | 1800145436 | 162.00 | 2010-02-12

0010021791 | 1600007737 | -12.00 | 2010-03-15

0014066147 | 1800119068 | 1,684.80 | 2010-03-12

0014066147 | 1800123702 | 1,684.80 | 2010-02-12

0014066147 | 1600007980 | -1,300.80 | 2010-02-15

0014066147 | 1600007719 | -1,286.40 | 2010-03-15

I need to remove rows with negative invoices in a way that amount is summed with invoices which are not with negative amount. So that final result would look like:

A          | B          | C      | D

0010019991 | 1800149471 | 126.00 | 2010-03-12

0010019991 | 1800136388 | 162.00 | 2010-02-12

0010021791 | 1800132148 | 150.00 | 2010-03-12

0010021791 | 1800145436 | 162.00 | 2010-02-12

0014066147 | 1800123702 | 782.40 | 2010-02-12