(a) The rate of contribution payable by members shall be:

(1)

(A) In the case of a member in Group 1, five percent (5%) of the member's earnable compensation;

(B) In the case of a member in Group 2, five and one-half percent (5.5%) of the member's earnable compensation;

(C) In the case of a member in Group 3 or 4, five and one-half percent (5.5%) of the member's covered compensation, plus seven percent (7%) of the part of the member's earnable compensation in excess of the member's covered compensation; and

(D) Notwithstanding any law to the contrary, a state judge participating in the retirement system as a Group 1 member may voluntarily elect to contribute five and one-half percent (5.5%) of the member's earnable compensation, plus seven percent (7%) of the part of the member's earnable compensation in excess of the member's covered compensation. It is further provided that prior to September 1, 1990, voluntary contributions under this subsection (a) will not be used to increase any benefits payable under chapters 34-37 of this title. Upon termination of membership, these voluntary contributions are refundable;

(2) A member participating in the optional retirement program as provided under chapter 25, part 2 of this title shall contribute five percent (5%) of the member's covered compensation, plus five and one-half percent (5.5%) of the part of the member's earnable compensation in excess of the member's covered compensation;

(3) An employee in the employ of a political subdivision or participating under chapter 35, part 2 of this title shall contribute:

(A) In the case of Group 1 members, five percent (5%) of the member's covered compensation, plus five and one-half percent (5.5%) of the part of the member's earnable compensation in excess of the member's covered compensation; and

(B) In the case of a Group 2 member, five and one-half percent (5.5%) of the member's covered compensation, plus seven percent (7%) of the part of the member's earnable compensation in excess of the member's covered compensation;

(4) The governing body of a political subdivision may authorize by resolution and accept the liability for its employees to contribute:

(A) In the case of a member in Group 1, five percent (5%) of the member's earnable compensation; and

(B) In the case of a member in Group 2, five and one-half percent (5.5%) of the member's earnable compensation;

(5) Notwithstanding any other provisions to the contrary, for all services rendered after September 1, 1974, the rate of contribution payable by a member of the superseded Tennessee judges' retirement system, the retirement system for county paid judges of Tennessee, the attorneys general retirement system of Tennessee, the public service commissioners' retirement system and the Tennessee retirement system for county officials shall be eight percent (8%) of gross wages;

(6) The county legislative body may, by resolution duly adopted, contribute for all eligible county officials up to three percent (3%) of the eight percent (8%) of gross wages specified by subdivision (a)(5) as contribution to the superseded Tennessee retirement system for county officials; and

(7) For service rendered from and after July 1, 1989, the county legislative body of any political subdivision that has adopted the noncontributory provisions of § 8-34-206 may, by resolution duly adopted, assume the total amount of contributions required under this section for all eligible county officials and county judges participating in the Tennessee consolidated retirement system or a superseded retirement system.

(b) A noncontributory member as defined in § 8-34-206 shall cease to make and have deducted from the noncontributory member's compensation employee contributions as required under this part; provided, that such contribution is not in excess of five percent (5%) of earnable compensation. A noncontributory member who was contributing at more than five percent (5%) prior to July 1, 1981, shall continue to make and have deducted from the noncontributory member's compensation the difference between the contribution rate applicable for the noncontributory member's group or classification and five percent (5%). The rates of contributions payable by a noncontributory member as defined by § 8-34-206, shall be:

(1) In the case of a Group 1 member or a transferred Class B member, zero percent (0%) of the member's earnable compensation;

(2) In the case of a prior Class B member, two percent (2%) of the member's earnable compensation;

(3) In the case of a prior Class C member, six and sixty-three hundredths percent (6.63%) of the member's earnable compensation;

(4) In the case of a Group 2 member, one half of one percent (0.5%) of the member's earnable compensation;

(5) In the case of a Group 3 member who is a noncontributory member under § 8-34-206, one half of one percent (0.5%) of the member's covered compensation, plus two percent (2%) of the part of the member's earnable compensation in excess of the member's covered compensation;

(6) In the case of a prior class public service commissioner, three percent (3%) of the member's earnable compensation;

(7) In the case of a prior class member of the attorneys general retirement system presently employed by the executive branch of the state and compensated under the compensation plan administered by the department of human resources or employees of the general assembly who are classified under § 8-34-101, three percent (3%) of the member's earnable compensation; and

(8) In the case of a prior class member of the attorneys general retirement system who is a noncontributory member under § 8-34-206, three percent (3%) of the member's earnable compensation.