20 C.F.R. § 229.2
The following definitions are used in this part:
Annuity means a payment under the Railroad Retirement Act due and payable to an entitled claimant for a calendar month and made to him or her on the first day of the following month. The recipient of an annuity is called an annuitant.
Average Indexed Monthly Earnings or AIME means the average of the employee's monthly creditable earnings in both railroad and social security covered employment in the years used in computing the Primary Insurance Amount, after the earnings are adjusted or "indexed". The indexing is a means of expressing prior years earnings in terms of their current dollar value. It is based on increases in the average wages of all wage earners from 1951 although the second year before the year the worker dies or becomes eligible for benefits.
Contribution and benefit base means the maximum earnings used in computing a social security benefit under section 230 of the Social Security Act.
1974 Act means the Railroad Retirement Act approved October 16, 1974, including all amendments.
Railroad formula rate means the amount computed in accord with the regular railroad computations (sections 3(a), 3(b) and 3(h) of the Railroad Retirement Act).
Retirement age means age 65, with respect to an employee or spouse who attains age 62 before January 1, 2000 (age 60 in the case of a widow(er), remarried widow(er) or surviving divorced spouse). For an employee or spouse who attains age 62 (or age 60 in the case of a widow(er), remarried widow(er), or surviving divorced spouse) after December 31, 1999, retirement age means the age provided for in section 216(l) of the Social Security Act.
20 C.F.R. § 229.2