This document contains final regulations that provide the method to be used to adjust the applicable Federal rates (AFRs) to determine the corresponding rates under section 1288 of the Internal Revenue Code (Code) for tax-exempt obligations (adjusted AFRs) and the method to be used to determine the long-term tax-exempt rate and the adjusted Federal long-term rate under section 382. For tax-exempt obligations, the regulations affect the determination of original issue discount under section 1273 and of total unstated interest under section 483. In addition, the regulations affect the determination of the limitations under sections 382 and 383 on the use of certain operating loss carryforwards, tax credits, and other attributes of corporations following ownership changes.