Report on Compensation Budget Utilization

We have to develop a report on Budget Pool Utilization by Business Units showing following fields:

Total Budget, Budget Utilized, Available Budget, Total Headcount, Headcount Utilized, BU Name.

The values needs to be grouped by BU's.

The Budget Allocation Type is Percent (Managers). My question is since the budget is allocated to managers and not associates. What if the Manager has associates belonging to different BU's. How will the budget allocated to manager be divided between employees to be shown in report. Or this report is not feasible for Manager Type allocation and only for Employee-Amount type allocation.