Excel 2007 : Calculating elapsed time which meet two criteria

I have a table full of data (id, time, state). What I want to do for data with the same id, is look for state A, and state C, and figure out the time elasped between them. I somewhat know how to do it if it was from state A to B, as they would be beside each in the table, but if it jumps a state, I don't really know where to start.

Pointers in the general direction would be appreciated. I'm not actually sure if this is possible to do, since I have only done simple calculations that used the line before or after.

Thanks.