I'm trying to do a sum within a sum in a pivot table. For example I'm doing the sales by different customer groups over a 10 year period. I want to be able to look at those customers with sales as a whole but also by individual years or only summing say the last 3 years. Also is there a way to look at the same information on the products they buy and combing all the sales data on that side if someone was looking at related products and wanted to combine certain product lines.