Rebate Credit Memo relevant for other rebate

Hello,

We are using rebate agreements but here we have the particulary that one customer could have more than one rebate agreement in a period, and the last rebate agreement that you create the final settlement have to consider the others credit memo of the rebates paid.

So, I have a customer who have 2 rebates:

RA 1: Valid from: 3/6/14 to 10/6/14

RA 2: Valid from: 1/6/14 to 30/6/14

I pay the RA1 with a credit memo of $1000.

Then the sales volume of the second rebate (RA2) is $4000, but as the RA1 = $1000 you have to consider this credit memo into the RA2, so you will pay a credit memo of $4000 - $1000 = $3000 for the RA2.

Could someone help me with this?

It is possible to do in SAP ?

thanks in advance.

Alejandro.