Excel categories and subcategories

aasmaestro 

I would always suggest having a single consolidated database as the first step for something like this. So that's what I've created. (It is always easier for both you, the user, and Excel to work from a consolidated database. It is easier--simpler formulas--to parse data into those separate categories, for example, via formula or Pivot Table, rather than separating them at the start (as we would have done back in the pencil and paper days, on ledger sheets) .

From that consolidated database it's very easy to take one of two different approaches to summarizing the data.

1. Perhaps the easiest is to use the Pivot Table, which will allow you to be selective, if desired, by product category (see the drop down selection at the top of the Pivot Table tab).
2. The other is a formula that SUMs FILTERed results for each corporation for each column. You'll see that formula in your original "Top Customer -- Console" tab

I don't pretend that this is the complete answer -- the results aren't sorted based on highest quantities -- but it's a start and gives you an introduction to two quite different ways to approach the situation.