Susan - you are correct, you have to own SalesAnalysis. Besides being an easier table to deal with when writing custom reports, it has (at least) one other major feature. It is the only place you can go to create a report that shows paid invoices BY ITEM. This is crucial if you are paying commissions based on collections and not based on billings.

Andrew - I consider those formulas to be using linked tables. While not difficult to learn how, it is one step more advanced than selecting fields from the driving table.

Steve