Prorating Certain Reimbursement Wagetype for LOP

Dear Experts,

For a set of wagetypes like Gift Coupon, Newspaper,Soft furnishing, SAN,meal voucher, Car maintenance-driver I've to prorate the value as per Loss of Pay.

Ex: If for Gift coupon monthly eligibility is 3000 and there are 5 LOP in that month for that employee, system should pay 2500 instead of 3000.

Regards,

NBN