The Board is hereby authorized and directed to select two actuaries, one from recommendations made by representatives of employees and the other from recommendations made by representatives of employers as defined in paragraph (i) of section
231
(a)(1) of this title. These actuaries, along with a third who shall be designated by the Secretary of the Treasury, shall be known as the Actuarial Advisory Committee with respect to the Railroad Retirement Account. The actuaries so selected shall hold membership in the American Academy of Actuaries and shall be qualified in the evaluation of pension plans: Provided, however, That these requirements shall not apply to any actuary who served as a member of the Committee prior to January 1, 1975. The Committee shall examine the actuarial reports and estimates made by the Board and shall have authority to recommend to the Board such changes in actuarial methods as they may deem necessary. The compensation of the members of the Committee, exclusive of the member designated by the Secretary, shall be fixed by the Board on a per diem basis.