HELP with putting some formulas in a pivot table!

Hello!
I am new to using excel, I am still learning how to use it for my rehabilitation service as a tool to keep track of my interventions and income.
I managed to put together a pivot table that has my patients grouped in different paying categories and shows the services they attended.
What i would like to do is make my pivot calculate a percentage for each group and the amount they would have to pay by the end of the month.

Example:
My pivot table already shows that:
For the month of Oct. 2013 Patient John Doe (from the group of patients that have an insurance deduction of 75%) had done 4 Physical therapy and 8 Hydrotherapy intervention.

I want it to calculate also:
How much they have to pay by group and by individual knowing the cost / intervention or / subscription

I'm probably having some difficulties in explaining myself but it must be really simple it's just that i can't figure it out.

I would really appreciate if you could land a hand

Thank you!

You get better help if you add manualy the result in your sheet.

I think there is confidential information in your data.

If so, please post an new workbook without confidential information.