Group Number Variable

I would like a group number variable formula to be added as a feature to Crystal Reports. This is how it would work:

For example, You have a sum of records for a group called payroll. The total is $20,000. Payroll is comprised of FICA, Medicare, and Salary etc. You want to add a budget amout for this group using a group number variable. The budget amount is $20,000. This budget amount would remain static for this group. The difference would be sum of records payroll group- group number variable which is $20,000 - 22,000=-2,000. Right now the maxinium function and manual running totals have to be used to arrive at the same figure. The group number variable could be used in cross tabs as well. Does anyone know if something like this is being planned?

Seán