Hi,
That's almost it, there's only one point that i didn't explain in my opening post.
The Sum of F1 should only be calculated when the month=1.
The Sum of F2 should only be calculated when the month=2.
The Sum of F3 should only be calculated when the month=3.
I modified my example data, only the values in bold should be calculated:
| CAT | MONTH | F1 | F2 | F3 |
| 1 | 1 | 1 | 2 | 5 |
| 1 | 1 | 6 | 3 | 6 |
| 1 | 1 | 4 | 5 | 7 |
| 1 | 1 | 2 | 6 | 8 |
| 2 | 1 | 3 | 7 | 3 |
| 2 | 1 | 4 | 8 | 2 |
| 2 | 1 | 5 | 3 | 3 |
| 2 | 2 | 2 | 2 | 5 |
| 2 | 2 | 3 | 3 | 6 |
| 3 | 2 | 5 | 5 | 7 |
| 3 | 2 | 6 | 6 | 8 |
| 3 | 2 | 7 | 7 | 9 |
| 3 | 2 | 8 | 8 | 7 |
| 3 | 2 | 9 | 9 | 2 |
| 3 | 3 | 3 | 7 | 1 |
| 4 | 3 | 5 | 8 | 2 |
| 4 | 3 | 6 | 9 | 3 |
| 4 | 3 | 7 | 2 | 4 |
| 4 | 3 | 8 | 3 | 5 |
| 5 | 3 | 8 | 5 | 6 |
