(a) Except as otherwise provided in this section, a member’s contribution rate is 5% of the part of the member’s earnable compensation that exceeds the taxable wage base for each year.

(b) The contribution rate of a member who is subject to the contributory pension benefit under Part II of this subtitle is 2% of the member’s earnable compensation.

(c) The contribution rate of a member who is subject to the Alternate Contributory Pension Selection under Part III of this subtitle is:

(1) 3% of the member’s earnable compensation received from July 1, 2006 to June 30, 2007, both inclusive;

(2) 4% of the member’s earnable compensation received from July 1, 2007 to June 30, 2008, both inclusive;

(3) 5% of the member’s earnable compensation received from July 1, 2008 to June 30, 2011, both inclusive; and

(4) 7% of the member’s earnable compensation received on or after July 1, 2011.

(d) The contribution rate of a member who is subject to the reformed contributory pension benefit under Part IV of this subtitle is 7% of the member’s earnable compensation.