Article Title: OPM: FERS Annuity Supplement
Snippet of Article: "...The special retirement supplement is paid in addition to gross monthly Federal Employees Retirement System (FERS) annuity benefits. It represents what you would receive for your FERS civilian service from the Social Security Administration (SSA) and is calculated as if you were eligible to receive SSA benefits on the day you retired. Eligibility for the annuity supplement continues until the earlier of (1) the last day of the month before the first month for which you would be entitled to actual Social Security benefits or (2) the last day of the month in which you reach age 62. ..."
Source: www.opm.gov