Automatic margin percentages in pivot table when expanding cell

Hi,

I have some pivot tables in Excel from a SQL Server 2010 database.

I enclosed an attachment to make my point more clear (fictive data).

In my pivot I have Parent Project, Projectdescription and Department as dimension columns.
When opening my pivot the standard view is as shown but the user should have the possibility to expand the view using the plus-sign before projectdescription. Then the Departments are shown.
My problem lies within the margin calculation. What I would like is the margin (column F as a percentage of column E) per project. For every row the calculation should be F/E * 100. So e.g. (F10/E10) * 100, (F11/E11) * 100, (F12/E12) * 100 etc. etc. I can't make that work WITHIN the pivot table. I tried several formula options using a percentage, but all in vain. The percentages as shown in the attachment are calculated OUTSIDE the pivot, but when clicking on the plus-sign before Projectdescription the percentages become completely fuzzy starting from that cell downwards.

Is there a way to calculate the percentages WITHIN the pivot table the way I would like it USING THE STANDARD FUNCTIONALITY IN EXCEL.
It sounds very simple but I didn't figure it out yet!

I installed power pivot .... but still no solution.


Thanks!

Michiel