Section 838.621 - Prorata share(a)Pro rata share means one-half of the fraction whose numerator is the number of months of Federal civilian and military service that the employee performed during the marriage and whose denominator is the total number of months of Federal civilian and military service performed by the employee through the day before the effective date of phased retirement or separation for retirement, as applicable to the annuity calculation. In the computation of the division of phased retirement annuity and a composite retirement annuity, a pro rata share will be computed through the day before the effective date of an employee's phased retirement for the computation of the division of a phased retirement annuity and then recomputed for division of the composite retirement annuity under §§ 831.1742 and 848.502 .(b) A court order that awards a former spouse a prorata share of an employee annuity or a refund of employee contributions by using the term "prorata share" and identifying the date when the marriage began satisfies the requirements of §§ 838.305 and 838.504 and awards the former spouse a prorata share as defined in paragraph (a) of this section.(c) A court order that awards a portion of an employee annuity as of a specified date before the employee's phased retirement or retirement awards the former spouse a pro rata share as defined in paragraph (a) of this section.(d) A court order that awards a portion of the "value" of an annuity as of a specific date before retirement, without specifying what "value" is, awards the former spouse a prorata share as defined in paragraph (a) of this section.57 FR 33574, July 29, 1992, as amended at 79 FR 46627 , Aug. 8, 2014