Cognos TM1

I need an TM1 Expert that can help me solving a problem. I have two identical Dimension hierarchies, "Expense Account" and "Income Account, and a measure Dimension with one element "Sales amount". Each Sale is assigned to an Expense Account and Income Account. Expense Account Hierarchy = Income Account Hierarchy: A - B - C D - E Example for two Sales delivered as a cvs file: Expense Account; Income Account; Sales Amount B; C; 30 C; E; 25 After loading this file to the Sales Cube, I got this result: Expense Account Hierarchy on the row, Measure Sales Amount on column: A (55) - B (30) - C (25) D (0) - E (0) My requirement is, that for consolidated node (A), the amount of B should be eliminated, because the Income account is in the same hierarchy as the Expense Account (Both have a common parent (A)). So the result I'm expected is like this: A (25) > B is not considered while summing up the consolidation. - B (30) - C (25) D (0) - E (0) That should be achievable using a C:Level Rule, but I don't know exactly how.