I think what James is looking for is similar to what I use to calculate a clients needs based on how much of what type of debris they handle. Yo look at your total waste stream and make as accurate a determination as possible how many different things make up the total and then figure the percentages of each constituent. I use this to determine what type of sorting technology will work better for a potential client.
IE: Metals, glass, insulation, drywall, paper, OCC, wood (treated and untreated), concrete etc.