This excerpt taken from the AN 10-K filed Feb 17, 2010.
19. CHARGEBACK RESERVES
We may be charged back for commissions related to financing, insurance, or vehicle protection products in the event of early termination of the contracts by customers (chargebacks). These commissions are recorded at the time of the sale of the vehicles, net of an estimated liability for chargebacks. The following is a rollforward of our estimated chargeback liability for each of the three years presented in our Consolidated Financial Statements:
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS