In other situations, the regulatory process can result in the accounting recognition of a liability. This usually occurs when regulators mandate that refunds be paid to customers, which must be accrued when probable and reasonably estimable, per FAS 5, Accounting for Contingencies. Furthermore, regulatory rates may be set at a higher level, in order to recover costs expected to be incurred in the future, subject to the caveat that such amounts will be refunded to customers if it later becomes apparent that actual costs incurred were less than expected. In such cases, the incremental rate increase related to recovery of future costs must be accounted for as a liability (unearned revenue), until the condition specified is satisfied. Finally, regulators may stipulate that a gain realized by the utility will be returned to customers over a specified future period; this will be accounted for by accrual of a liability rather than by recognition of the gain for accounting purposes.