; (2) in paragraph (2), by striking the period at the end and inserting ; and ; and (3) by inserting after paragraph (2) the following: (3) which shall provide the overall change in Postal Service productivity and the resulting effect of such change on overall Postal Service costs during such year, using such methodologies as the Commission shall by regulation prescribe, if necessary. . (g) POSTPlan study (1) In general Beginning not later than 30 days after the date of enactment of this Act, the Inspector General of the Postal Service shall conduct a 1-year review of the impacts of the POSTPlan post office restructuring plan on Postal Service expenses, revenue, and retail service provision. (2) Content In conducting the review under paragraph (1), the Inspector General shall examine— (A) changes in the costs for the provision of Postal Service operated retail service, both nationwide and in the aggregate for each of the Level 2, Level 4, Level 6, and Level 18 post offices for which the hours, functions, or responsibilities changed as a result of the POSTPlan initiative before and after the implementation of the POSTPlan initiative; (B) changes in revenue received by Postal Service operated retail service, both nationwide and in the aggregate for each of the Level 2, Level 4, Level 6, and Level 18 post offices for which the hours, functions, or responsibilities changed as a result of the POSTPlan initiative before and after the implementation of the POSTPlan initiative; (C) a determination of the relative cost savings, taking into account any changes in revenue earned, realized on an annual basis for Level 2, Level 4, Level 6, and Level 18 offices each in the aggregate and any trends in such cost savings; (D) the relative impact on retail access to postal services for individuals served by Level 2, Level 4, Level 6, and Level 18 offices each in the aggregate