Sumproduct in a Pivot Table?

[Rupaner]

Hello,

I have a pivot table that shows me the return of few financial aplications ("ÍNDICE 1" and "ÍNDICE 2"), to do this I had to set this both collumn as a "sum" and changed the format to %.

Everthing is ok... the problem is that I can´t sum this values on the total of the table/group, I need to make a median average and not the total os this values.
So, how can I do this on the pivot table?

*the orange cells is the place who should bring me the median average (now it´s showing me the total)

Thanks!