Many thanks,
but the problem is that the result for NumberOfSales is Count(SalesOld.SalesManID)*Count(SalesNew.SalesManID)*2.
For example one salesman has 35 entries in SalesNew and 334 in SalesOld.
The result of the Count(SalesOld.SalesManID)+Count(SalesNew.SalesManID) is 35*334*2=23380
CU
Thorsten