Upon retirement from service, as provided for in RCW
41.40.180 or
41.40.210, a member shall be eligible for a service retirement allowance computed on the basis of the law in effect at the time of retirement, together with such post-retirement pension increases as may from time to time be expressly authorized by the legislature. The service retirement allowance payable to members retiring on and after February 25, 1972 shall consist of:
(1) An annuity which shall be the actuarial equivalent of his or her additional contributions made pursuant to RCW
41.40.330(2).
(2) A membership service pension, subject to the provisions of subsection (4) of this section, which shall be equal to two percent of his or her average final compensation for each service credit year or fraction of a service credit year of membership service.
(3) A prior service pension which shall be equal to one-seventieth of his or her average final compensation for each year or fraction of a year of prior service not to exceed thirty years credited to his or her service accounts. In no event, except as provided in *this 1972 amendatory act, shall any member receive a retirement allowance pursuant to subsections (2) and (3) of this section of more than sixty percent of his or her average final compensation: PROVIDED, That no member shall receive a pension under this section of less than nine hundred dollars per annum if such member has twelve or more years of service credit, or less than one thousand and two hundred dollars per annum if such member has sixteen or more years of service credit, or less than one thousand five hundred and sixty dollars per annum if such member has twenty or more years of service credit.
(4) Notwithstanding the provisions of subsections (1) through (3) of this section, the retirement allowance payable for service where a member was elected or appointed pursuant to Articles II or III of the Constitution of the state of Washington or RCW
48.02.010 and the implementing statutes shall be a combined pension and annuity. Said retirement allowance shall be equal to three percent of the average final compensation for each year of such service. Any member covered by this subsection who upon retirement has served ten or more years shall receive a retirement allowance of at least one thousand two hundred dollars per annum; such member who has served fifteen or more years shall receive a retirement allowance of at least one thousand eight hundred dollars per annum; and such member who has served twenty or more years shall receive a retirement allowance of at least two thousand four hundred dollars per annum: PROVIDED, That the initial retirement allowance of a member retiring only under the provisions of this subsection shall not exceed the average final compensation upon which the retirement allowance is based. The minimum benefits provided in this subsection shall apply to all retired members or to the surviving spouse of deceased members who were elected to the office of state senator or state representative.