Percentage Rank in webI

Hi Gurus,

I need to do a Percentage Rank in WebI.. just like PercentageRank() in Excel.

I have Date and WeekAgg from SQL . Report is based on Universe and did some work around on few formulas on Percent Rank but in vain.

Rank(WeekAgg)/ Runningcount(WeekAgg) and Nofilter() option also did not work.

Any help on this would be appreciated.

Thanks,

Jothi