Benefit variable rate Calculation Issue

Inviting Experts suggestions for dynamic calculations in Benefit Module. We have requirement to calculate benefit rate basis the logic 'Salary multiplied by a Multiplier which varies based on Age of Participant' per thousand of the amount. We have used Variable Rates to achieve this for all age groups. These Variable Rates are all attached to the Standard Rate. However upon benefit processing, the multiplier is not showing effect.

Has anyone faced such issue before? Or if there are any workarounds, please suggest.

Thanks,

Tanya