31 U.S.C. § 774: Survivor annuities

“allowable military service” means honorable active service of not more than 5 years in an armed force (including service in the National Guard when ordered to active duty for the United States Government), when the service is not creditable in computing another annuity. “other prior allowable service” means civilian service as an officer or employee of the Government or District of Columbia government not covered by subsection (d)(1) of this section. “congressional employee” has the same meaning given that term in section 2107 of title 5 . makes an election under section 773 of this title ; dies in office or while receiving an annuity under section 772 of this title ; had at least 18 months of civilian service at death computed under subsections (a) and (d) of this section; and had deductions or deposits under section 773 of this title made for the last 18 months of civilian service. only by a spouse, the surviving spouse shall receive an annuity computed under subsection (d) of this section beginning on the death of the Comptroller General or retired Comptroller General or when the spouse is 50 years of age, whichever is later; 10 percent of the average annual pay computed under subsection (d)(1) of this section; or 20 percent of the average annual pay computed under subsection (d)(1) of this section, divided by the number of dependent children; or the annuity a surviving spouse would be entitled to receive under clause (2) of this subsection, divided by the number of dependent children; 20 percent of the average annual pay computed under subsection (d)(1) of this section; or 40 percent of the average annual pay computed under subsection (d)(1) of this section, divided by the number of dependent children. service as Comptroller General or a member of Congress; and prior allowable military service; and not more than 15 years of prior allowable service as a congressional employee; plus .75 percent of the average pay computed under clause (1) of this subsection times the number of years of other allowable service. A surviving spouse’s annuity may not be more than 50 percent nor less than 25 percent of the average annual pay computed under subsection (d)(1) of this section. If a Comptroller General does not make the deposit under section 773(b) of this title , a surviving spouse’s annuity shall be credited with the service during which a deposit was not made, unless the spouse elects not to have the service credited. However, the annuity shall be reduced by 10 percent of the amount of the unpaid deposit, computed on the date the Comptroller General or retired Comptroller General dies.