Allowing tables to feed a metric for a scorecard Merged

I'm trying to figure out a way to build a metric for a scorecard that is driven from a table or table data. I have a scorecard that is (evidence)*(impact)*(buyerflag+userflag+competitorflag+strategyflag). The flags all have values 0 or 1, and the impact will be a rating 1-5. The tricky part is the evidence metric. What we'd like to be able to do is to tally particular customers that have requested the feature and weight them according to the fraction of revenue they bring into the product. E.g. if the feature has been requested by CustomerA with 13% revenue share, CustomerD with 8% revenue share, and CustomerF with 3% revenue share, but CustomersB,C,E,G, and H have not requested it, this metric would be 24 (percent). However, I don't want to build a metric with 150 customers in it. Rather, I'd like to have a table somewhere in the system that I can build this metric from.