I have a simple pivot. In my Rows area I have Strategy, in Columns I have "LBB Acct", and in my values I have "Sum of CP FY18 FTE".

For "LBB Acct" there are 5 different flavors: FTEABF, FTEABU, FTECAP, FTEACN, FY 2018 CAP
I also have a "Grand Total" column.

I want to construct my pivot to have a calculated field (or calculated item) which would be the sum of the first 4. I'd like that to show in place before the 5th ("FY 2018 CAP"), and have the Grand Total show the difference between the first 4 and the 5th.

Can I do that in my pivot, or do I need to do it in my source data?

To do it in my pivot, how to?

I'll post an example if I must, but would prefer not to as the WB doesn't belong to me and I'm reluctant to share data that's not mine.