CiviReport summary for pledge that's a summary

Hi Deepak - need your help on this.

We have a need for a pledge summary report that gives pledge amount aggregation & group bys & such like. I've pretty much got the report (attached) apart from 1 problem::

There is already a Pledge Summary report - except it's actually a pledge detail report!! The existing Pledge report doesn't act like a pledge summary so ideally would be renamed to detail & some sort of SQL would sort out people's existing installs - but is that too hard?

(Dgg pointed me to you