If you are building SSRS 2008 reports using Business Intelligence Developer Studio from a SSAS Cube, you will want to pay close attention. For some reason, when you go through the wizard and select to have sub-totals, SSRS defaults to using SUM on the sub-total line. This causes the detail lines to sub-total. However, we all know one of the great powers of SSAS is that it can be configured to properly aggregate at all levels. You will have to go into the expression and change the SUM to AGGREGATE on all except the detail line.