My apologies, didn't quite catch the gist.
Would be helpful if you could post a workbook of fake data
in same format as what you have described:
It's not clear to me which values are changing when
[CUST] and [FICO] filters are used. Are both [OrigAVG]
and the Period values changing with the filters?
Also would be grateful for a description of the calculation
you are using for the weighted average.