§ 8421. Annuity supplement

(a)
(1) Subject to paragraph (3), an individual shall, if and while entitled to an annuity under subsection (a), (b), (d), or (e) of section 8412, or under section 8414 (c), also be entitled to an annuity supplement under this section.
(2) Subject to paragraph (3), an individual shall, if and while entitled to an annuity under section 8412 (f), or under subsection (a) or (b) of section 8414, also be entitled to an annuity supplement under this section if such individual is at least the applicable minimum retirement age under section 8412 (h).
(3)
(A) An individual whose entitlement to an annuity under section 8412 or 8414 does not commence before age 62 is not entitled to an annuity supplement under this section.
(B) An individual entitled to an annuity supplement under this section ceases to be so entitled after the last day of the month preceding the first month for which such individual would, on proper application, be entitled to old-age insurance benefits under title II of the Social Security Act, but not later than the last day of the month in which such individual attains age 62.
(b)
(1) The amount of the annuity supplement of an annuitant under this section for any month shall be equal to the product of—
(A) an amount determined under paragraph (2), multiplied by
(B) a fraction, as described in paragraph (3).
(2) The amount under this paragraph for an annuitant is an amount equal to the old-age insurance benefit which would be payable to such annuitant under title II of the Social Security Act (without regard to sections 203, 215(a)(7), and 215(d)(5) of such Act) upon attaining age 62 and filing application therefor, determined as if the annuitant had attained such age and filed application therefor, and were a fully insured individual (as defined in section 214(a) of such Act), on January 1 of the year in which such annuitant’s entitlement to any payment under this section commences, except that the reduction of such old-age insurance benefit under section 202(q) of such Act shall be the maximum applicable for an individual born in the same year as the annuitant. In computing the primary insurance amount under section 215 of such Act for purposes of this paragraph, the number of elapsed years (referred to in section 215(b)(2)(B)(iii) of such Act and used to compute the number of benefit computation years) shall not include years beginning with the year in which such annuitant’s entitlement to any payment under this section commences, and—
(A) only basic pay for service performed (if any) shall be taken into account in computing the total wages and self-employment income of the annuitant for a benefit computation year;
(B) for a benefit computation year which commences after the date of the separation with respect to which entitlement to the annuitant’s annuity under this subchapter is based and before the date as of which such annuitant is treated, under the preceding sentence, to have attained age 62, the total wages and self-employment income of such annuitant for such year shall be deemed to be zero; and
(C) for a benefit computation year after age 21 which precedes the separation referred to in subparagraph (B), and during which the individual did not perform a full year of service, the total wages and self-employment income of such annuitant for such year shall be deemed to have been an amount equal to the product of—
(i) the average total wages of all workers for that year, multiplied by
(ii) a fraction—
(I) the numerator of which is the total basic pay of the individual for service performed in the first year thereafter in which such individual performed a full year of service; and
(II) the denominator of which is the average total wages of all workers for the year referred to in subclause (I).
(3) The fraction under this paragraph for any annuitant is a fraction—
(A) the numerator of which is the annuitant’s total years of service (rounding a fraction to the nearest whole number, with 1/2 being rounded to the next higher number), not to exceed the number under subparagraph (B); and
(B) the denominator of which is 40.
(4) For the purpose of this subsection—
(A) the term “benefit computation year” has the meaning provided in section 215(b)(2)(B)(i) of the Social Security Act;
(B) the term “average total wages of all workers”, for a year, means the average of the total wages, as defined and computed under section 215(b)(3)(A)(ii)(I) of the Social Security Act for such year; and
(C) the term “service” does not include military service.
(c) An amount under this section shall, for purposes of section 8467, be treated in the same way as an amount computed under section 8415.