(1) The normal rates of contribution of members shall be based on sex and age at time of entry into the system, which age shall be the age at the birthday nearest the date of such entry.

(2) The normal rates of contribution for miscellaneous personnel shall be so fixed as to provide an annuity which, together with the pension provided by the city, shall produce as nearly as may be, a retirement allowance at the age of sixty-two years, of one and one-third percent of the final compensation multiplied by the number of years of service of the retiring employee. The normal rate established for age sixty shall be the rate for any member who has attained a greater age before entrance into the retirement system and the normal contribution established for age twenty-four shall be the rate for any member who enters the system at an earlier age.

(3) The normal rates of contribution for uniformed personnel shall be so fixed as to provide an annuity which, together with the pension that would be derived from equal contributions by the city, shall produce as nearly as may be for members who enter service at age thirty-seven or below, a retirement allowance, at age fifty-five with twenty-five or more years of service, or at an age greater than fifty-five after twenty-five years of service, equal to fifty percent of final compensation; and for members entering service at ages over thirty-seven, a retirement allowance at age sixty-two which shall be the same proportion of fifty percent of final compensation as the member's actual years credited bear to twenty-five years. The normal rate established for age fifty shall be the rate for any member who has attained a greater age before entrance into the retirement system.

(4) Subject to the provisions of this chapter, the board shall adopt rules and regulations governing the making of deductions from the compensation of employees and shall certify to the proper officials in each city the normal rate of contribution for each member provided for in subsections (2) and (3) of this section. The proper officials in each city shall apply such rate of contribution to the full compensation of uniformed personnel and to so much of the compensation of miscellaneous personnel as does not exceed three hundred dollars per month, or four hundred dollars per month, or to any increased amount of such compensation as to members whose member cities have duly elected to increase the limitation provided for in subsection (12) of RCW 41.44.030 and shall certify to the board on each and every payroll the total amount to be contributed and shall furnish immediately to the board a copy of each and every payroll; and each of said amounts shall be forwarded immediately to the board and the board shall credit the deduction shown on such payroll to individual accounts of the members represented on such payrolls.

(5) Every member shall be deemed to consent and agree to the contribution made and provided for herein, and shall receipt in full for his or her salary or compensation. Payment less said contributions shall be a full and complete discharge of all claims and demands whatsoever for the service rendered by such person during the period covered by such payment, except his or her claim to the benefits to which he or she may be entitled under the provisions of this chapter.

(6) Any member may elect to contribute in excess of the contributions provided for in this section in accordance with rules to be established by the board for the purpose of providing additional benefits, but the exercise of this privilege shall not place on the member city or cities any additional financial obligation. The board shall have authority to fix the rate of interest to be paid or allowed upon the additional contributions and from time to time make any necessary changes in said rate. Refunds of additional contributions shall be governed by the same rules as those covering normal contributions unless the board shall establish separate rules therefor.