Automated Partial Refund

I think it would be great if we could set up auto-refund features for partial refunds based on percentage. This would give a more detailed cancellation policy, in a short window before reservation, it could give a 50% refund. As a quick example, more than 4 hours before reservation, 100% automatic refund. Between 1 and 4 hours before reservation, 50% automatic refund. 1 hour or less before reservation time, no automatic refund. As it is right now, partial refunds based on percentage must be done manually.