Need to print sum of Position FTEs by Business Units in OTBI

Summary:We have a requirement in OTBI to fetch business unit name and Position FTEs. But we have to print the sum of FTEs grouping it by each business unit. We are using Workforce Management - Positions Real time subject area to fetch BU Name and Position FTE, but need to understand how do we print sum of FTEs w.r.t individual business unit.

Additionally, it would be helpful to know what is the logic used by system to fetch the Position FTE values?

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