There are a few ways to group. One of the easiest is just to select the fields in a legend and right-click "group".
However, since you have so many customers, it might be better to create a calculated field: Customer Type
IF CONTAINS([Customer Name], "External") THEN "Distributor"
ELSEIF CONTAINS([Customer Name], "Internal") THEN "Affiliate"
Now you can double-click Customer Type and double click sales and select pie chart (if you must ).
You can also crate a hierarchy my dragging the field Customer Type on top of Customer. Now when you add Customer Type to your view, it will have a "+" sign that you can click to drill down the the customer level.
Message was edited by: Jim Wahl Corrected error in formula.