SSRS: Summing Group totals

I have 3 groups. in group 3 I have the following calculation: =IIF(SUM(Fields!ViolationPoints.Value * Fields!TimeWeight.Value) > 30, 30, SUM(Fields!ViolationPoints.Value * Fields!TimeWeight.Value))

How can I then sum these totals in a group 1 field. Basically I get about 2 or 3 records in gorup 3 and 开发者_运维技巧I need to show the sum of that in gorup 1.

Thanks!

We need more information; are you using a Table to display your groups or are these simply calculations that you want to perform outside of the Tables?