(a) The definitions in paragraphs (b) through (e) of this section apply to this subpart.

(b) Amortization payments mean the amounts that the Postal Service is invoiced by the U.S. Office of Personnel Management to provide for the liquidation of the specific and supplemental unfunded liabilities by statutorily predetermined dates, as described in § 3030.182(a).

(c) Phase-in period means the period of time spanning the fiscal years of issuance of the first five determinations following January 14, 2021, as specified by the timing provisions in § 3030.181.

(d) Required minimum remittance means the minimum amount the Postal Service is required to remit during a particular fiscal year, as calculated under § 3030.184.

(e) Revenue collected under this subpart means the amount of revenue collected during a fiscal year as a result of all previous rate increases authorized under this subpart, as calculated under § 3030.184.

(a) This subpart allocates additional rate authority to provide the Postal Service with revenue for remittance towards the statutorily mandated amortization payments for supplemental and unfunded liabilities identified in § 3030.182. As described in § 3030.184, for retirement obligation rate authority to be made available, the Postal Service must annually remit towards these amortization payments all revenue collected under this subpart previously. The full retirement obligation rate authority, calculated as described in § 3030.183, shall be phased in over 5 fiscal years, taking into account changes in volume during the phase-in period. If combined with an equal rate increase on Competitive products, the compounded rate increase resulting from retirement obligation rate authority is calculated to generate sufficient additional revenue at the end of the phase-in period to permit the Postal Service to remit the entire invoiced amount of its amortization payments.

(b) Until the conclusion of the phase-in period, the Postal Service shall file a notice with the Commission by December 31 of each year that calculates the amount of retirement obligation rate authority that is eligible to be authorized under this subpart.

(c) The Commission shall review the Postal Service's notice and determine how much, if any, rate authority will be authorized under this subpart. Any rate authority allocated under this subpart:

(1) Shall be made available to the Postal Service as of the date of the Commission's determination;

(2) Must be included in the calculation of the maximum rate adjustment authority in the first generally applicable rate adjustment filed after the Commission's determination;

(3) Shall lapse if not used in the first generally applicable rate adjustment filed after the Commission's determination;

(4) Shall lapse if unused, within 12 months of the Commission's determination, however this paragraph (c)(4) shall not prohibit the Postal Service from making a stand-alone adjustment to one or two generally applicable rate cells, if such a case were to be followed by a broader rate adjustment in the class later in the same fiscal year; and

(5) May not be used to generate unused rate authority, nor shall it affect existing banked rate authority.

(a) The amounts of the amortization payments needed for the calculation of retirement obligation rate adjustment authority in § 3030.183 shall be obtained from notifications to the Postal Service by the Office of Personnel Management of annual determinations of the funding amounts specific to payments at the end of each fiscal year for Retiree Health Benefits as computed under 5 U.S.C. 8909a(d)(2)(B) and (d)(3)(B)(ii); the Civil Service Retirement System as computed under 5 U.S.C. 8348(h)(2)(B); and the Federal Employees Retirement System as computed under 5 U.S.C. 8423(b)(1)(B), (b)(2), and (b)(3)(B), filed with the Postal Service's section 3652 report.

(b) The values for market dominant revenue, total revenue and market dominant volumes needed for the calculation of retirement obligation rate authority in § 3030.183 shall be obtained from values reported in the Revenue, Pieces, and Weight report, filed by the Postal Service under § 3050.25 of this chapter.

(c) The values for additional rate authority previously provided under this subpart, if any, needed for the calculation of retirement obligation rate authority in § 3030.183 and the calculation of required minimum remittances under § 3030.184 shall be obtained from the Commission's prior determinations.

(a) Formulas. (1) The formula for calculating the amount of retirement obligation rate authority available under this subpart, described in paragraph (b)(1) of this section, is as follows:

(2) The formula for calculating the amount of previously authorized retirement obligation rate authority through fiscal year T, described in paragraph (b)(2) of this section, is as follows:

(b) Calculations. (1) The amount of retirement obligation rate authority available for a fiscal year shall be calculated in four steps. First, the ratio of the total amortization payment for the fiscal year under review to the total revenue in the fiscal year under review shall be added to 1. This sum represents the factor by which an equal increase in market dominant and competitive rates in the fiscal year under review would generate sufficient additional revenue to make the full amortization payment. It does not account, however, for any previous rate authority authorized under this subpart. The second step is therefore to subtract the proportion of the market dominant rate base resulting from previously authorized retirement obligation rate authority. That proportion is calculated using the formula in paragraph (a)(2) of this section as described in paragraph (b)(2) of this section. Third, to amortize the resulting amount of retirement obligation rate authority over the remainder of the phase-in period, the difference shall be raised to the power of the inverse of the number of determinations remaining in the phase-in period, including the current determination. Finally, 1 shall be subtracted from the result to convert from a proportional change in rates to a percentage of rate adjustment authority.

(2) The amount of previously authorized retirement obligation rate authority shall be calculated in two steps. First, the sums of 1 and the amount of retirement obligation rate authority authorized in each of the previous fiscal years shall be multiplied together. This product represents the compounded amount of such rate authority, expressed as a net rate increase. To express this product as a proportion of the market dominant rate base, the second step is to subtract the inverse of this product from 1.

(a) Minimum remittances. During each fiscal year subsequent to January 14, 2021, the Postal Service shall remit towards the liabilities identified in § 3030.182 an amount equal to or greater than the amount of revenue collected as a result of all previous rate increases under this subpart during the previous fiscal year, as calculated using the formulas in paragraph (b) of this section, as described in paragraph (c) of this section.

(b) Formulas. (1) The formula for calculating the amount of revenue collected under this subpart during a fiscal year, described in paragraph (c)(1) of this section, is as follows:

(2) The formula for calculating the prorated fraction of retirement obligation rate authority authorized in a particular fiscal year t that was in effect during the most recently completed fiscal year, described in paragraph (c)(2) of this section, is as follows:

(c) Calculations. (1) The amount of revenue collected under this subpart during a fiscal year, as calculated by the formula in paragraph (b)(1) of this section, shall be calculated in three steps. First, the sums of 1 and the amount of retirement obligation rate authority made available under this subpart during each previous fiscal year—prorated to account for mid-year price increases as described in paragraph (b)(2) of this section—shall be multiplied together. This product represents the proportion by which prices were higher during the most recently completed fiscal year as a result of retirement obligation rate authority. Second, to express this net price increase as a proportion of market dominant revenue, the inverse of this product shall be subtracted from 1. Finally, the result shall be multiplied by market dominant revenue for the fiscal year to change the proportion into a dollar amount.

(2)(i) The prorated fraction of retirement obligation rate authority authorized in a particular fiscal year that was in effect during the most recently completed fiscal year, as calculated by the formula in paragraph (b)(2) of this section, shall be a piecewise function of three parts. First, if the retirement obligation rate authority authorized in a particular year was not in effect during the most recently completed fiscal year, the prorated fraction shall be 0. Second, if the retirement obligation rate authority authorized in a particular year was in effect during the entirety of the most recently completed fiscal year, the prorated fraction shall be 1. Finally, if the retirement obligation rate authority authorized in a particular fiscal year was used to raise prices during the most recently completed fiscal year, the prorated fraction shall be the proportion of volume sent during the fiscal year after that rate increase went into effect.

(ii) The proportion in paragraph (c)(2)(i) of this section shall be calculated in four steps. First, the number of days of the fiscal quarter after and including the effective date of the price adjustment including the retirement obligation rate authority shall be divided by the total number of days in that fiscal quarter. This quotient determines the proportion of days in that quarter in which the higher rates were in effect. Second, that quotient shall be multiplied by the market dominant volume from that fiscal quarter to determine the amount of volume during the quarter receiving the higher rates. Third, that product shall be added to the market dominant volume from any subsequent quarters of the fiscal year because the volume in those quarters was also sent under the higher rates. Finally, this sum shall be divided by the total market dominant volume from the fiscal year to determine the proportion of annual volume sent after the rate increase went into effect.

(a) If any of the circumstances described in paragraphs (b) through (d) of this section occur, the Postal Service shall not be eligible for future retirement obligation rate authority under this subpart, and the Commission may commence additional proceedings as appropriate.

(b) If, subsequent to March 1, 2021, and prior to the end of the phase-in period, the Postal Service fails to timely file the notice required under § 3030.181(b);

(c) In any fiscal year in which retirement obligation rate authority was determined to be available under this subpart, the Postal Service fails to timely file under § 3030.122 for a rate increase including the full amount of retirement obligation rate authority authorized under this subpart during that fiscal year, to take effect prior to the end of that fiscal year; or

(d) In any fiscal year including or subsequent to the first fiscal year in which rate authority under this subpart was used to adjust market dominant rates, the Postal Service's total payments towards the supplemental and unfunded liabilities identified in § 3030.182 are not equal to or greater than the minimum remittance required for that fiscal year under § 3030.184(a).