SSRS calculation with dynamic colums in matrix
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I pull some data from a stored procedure (There is no other way to get this). I sort and group them in a matrix.

Interval Desc.............[State_Desc]...................................Total

[Interval_Desc]..........[Sum(State_Duration_Hours)].......[Sum(State_Duration_Hours)]

Total..........................[Sum(State_Duration_Hours)].......[Sum(State_Duration_Hours)]          

It has the following grouping:
row: Interval_Desc
Column: State_Desc
The Interval Description are my three shifts that are running. The State description are either running, down and other reasons. The total summs them all up. I now want to calculate a seperate column that takes the total and substracts my running and my offline times.

I tried with a new parent group and filtered just by 'running' and subtracted it from the total like this:

    =Sum(Fields!State_Duration_Hours.Value,"Interval_Desc")-Sum(Fields!State_Duration_Hours.Value)

The problem is the second state 'offline' is there any way i can calculate my NOT running time.

Thanks,
