in the case of a former spouse whose divorce from such employee became final on or before December 4, 1991, was married to such employee for not less than 10 years during periods of the employee’s service which are creditable under section 8411 of title 5, at least 5 years of which were spent outside the United States by both the employee and the former spouse during the employee’s service with the Agency; and

in the case of a former spouse whose divorce from such employee becomes final after December 4, 1991, was married to such employee for not less than 10 years during periods of the employee’s service which are creditable under section 8411 of title 5, at least 5 years of which were spent by the employee outside the United States during the employee’s service with the Agency or otherwise in a position the duties of which qualified the employee for designation by the Director under the criteria prescribed in section 2013 of this title.

is in writing, is signed by the parties, and is notarized;

has not been modified by court order; and

has been authenticated by the Director.

the annuity of such former spouse shall commence on the date on which the employee would qualify, on the basis of the employee’s creditable service, for benefits under subchapter II of chapter 84 of title 5 or on the date on which the disability annuity begins, whichever is later; and

the amount of the annuity of the qualified former spouse shall be calculated on the basis of the benefits for which the employee would otherwise qualify under subchapter II of chapter 84 of such title.

50 percent of the employee’s annuity under subchapter III of chapter 83 of title 5 or under subchapter II of this chapter (computed in accordance with section 302(a) of the Federal Employees’ Retirement System Act of 1986 or section 2157 of this title), multiplied by the proportion that the number of days of marriage during the period of the employee’s creditable service before the effective date of the election to transfer bears to the employee’s total creditable service before such effective date; and

if applicable, 50 percent of the employee’s benefits under chapter 84 of title 5 or section 2152(a) of this title (computed in accordance with section 302(a) of the Federal Employees’ Retirement System Act of 1986 or section 2157 of this title), multiplied by the proportion that the number of days of marriage during the period of the employee’s creditable service on and after the effective date of the election to transfer bears to the employee’s total creditable service after such effective date.

The survivor benefits payable under this subsection to a qualified former spouse shall include the amount payable under section 8442(b)(1)(A) of title 5 and any supplementary annuity under section 8442(f) of such title that would be payable if such former spouse were a widow or widower entitled to an annuity under such section.

Any calculation under section 8442(f) of title 5 of the supplementary annuity payable to a widow or widower of an employee referred to in section 2152(a) of this title shall be based on an “assumed CIARDS annuity” rather than an “assumed CSRS annuity” as stated in section 8442(f) of such title. For the purpose of this subparagraph, the term “assumed CIARDS annuity” means the amount of the survivor annuity to which the widow or widower would be entitled under subchapter II of this chapter based on the service of the deceased annuitant determined under section 8442(f)(5) of such title.

such former spouse elects to receive this survivor annuity instead of any other survivor benefit to which such former spouse may be entitled under subchapter IV of chapter 84 of title 5, or under another retirement system for Government employees by reason of the remarriage; and

any lump sum paid on termination of the annuity is returned to the Civil Service Retirement and Disability Fund.

50 percent of the employee’s annuity under subchapter III of chapter 83 of title 5 or under subchapter II of this chapter (computed in accordance with section 302(a) of the Federal Employees’ Retirement System Act of 1986 or section 2157 of this title), multiplied by the proportion that the number of days of marriage during the period of the employee’s creditable service before the effective date of the election to transfer bears to the employee’s total creditable service before such effective date; and