Accrual accounting requires that the loss resulting from the failure of credit customers to pay their bills should be estimated in the period in which sales are made but should not be recorded until the customer defaults because of the matching principle be recognized in the period in which the account receivable proves to be uncollectible because that is the only date when the loss will really be known be estimated and recorded in the period in which sales are made so that periodic expenses are matched with periodic revenues. not be recorded until cash is collected from the customer in settlement of the account because that is the only sure event