Want to display % of grand total in group header

Hi Experts!

I have been looking through Crystal Reports answers in the Knowledge base for over an hour and still haven't found my answer, so it's time to post a question.

I am running Crystal Reports XI.

I want to show the current part number's "Issued x Cost" value as a percentage of the total report's "Issued x Cost" value.  I want to display this number in the group header as "% of Total".

Please keep in mind that "Issued" is a summed value from many transactional records.  The "parttran.tranqty" is accumulating in the Detail line, which is suppressed.  The formula for "Issued x Cost":
Sum ({parttran.tranqty}, {part.partnum}) * {partcost.avgmaterialcost}

Right now my "% of Total" calc is as follows:
({@Issued x Cost} / {@Report Total}) * 100

Boiled down, here's how the "% of Total" is working NOW:
Value          %
---------     --------
100          100.00%  (% of 100)
200           66.66%   (% of 300)
300           50.00%  (% of 600)
400           40.00%  (% of 1000)
500           33.33%  (% of 1500)

Here's how I WANT it to work:
Value          %
---------     --------
100             6.66%  (% of 1500)
200           13.33%  (% of 1500)
300           20.00%  (etc)
400           26.66%
500           33.33%

Please let me know what other data I can provide you to help me figure this out.  Thank you!!
Crystal-Example.doc