It sounds like you want to calculate the sales by a specific salesperson as a percentage of a specific category (across all salespeople). If there are only a few departments, you could create formulas like this:
//{@prodcategA}:
if {table.prodcateg} = "A" then {table.sales}
//{@prodcategB}:
if {table.prodcateg} = "A" then {table.sales}
You could then write a percentage formula for each product category like this:
//{@percentA}:
sum({@prodcategA},{table.salesperson}) % sum({@prodcategA})
//{@percentB}:
sum({@prodcategB},{table.salesperson}) % sum({@prodcategB})
You could then format each to suppress if zero, and then move the formulas on top of each other so that only one result appears per product category in the same position each time.
If there are a lot of product categories, you could either write your report using a command as the datasource where you have the command return the report level sum by product category so that you can use it in a formula to calculate percent within salesperson groups, or you could insert a subreport in the product category group that is linked on product category (but NOT on salesperson) that returns a shared variable which sums the total sales for that category which can then be used in the percent calculation.
-LB