(a) Each participating employee shall contribute to the optional retirement plan a percentage of his or her earnable compensation as determined by the board of trustees which shall be not less than 5 nor more than 6 percent.

(b) The University System of Georgia shall contribute to the optional retirement plan on behalf of each participating employee the following:

(1) Prior to January 1, 1997, an amount equal to 4 percent of the participating employee's earnable compensation; and

(2) On and after January 1, 1997, an amount equal to the normal cost contribution determined by the board of trustees in accordance with the provisions of Code Section 47-3-48. The provisions of this subsection are subject to subsequent legislation; provided, however, that such legislation shall not provide for a rate of contribution lower than 4 percent.

(c) The participating employee's contribution required by the provisions of subsection (a) of this Code section may be made by a reduction in earnable compensation or by an employer pickup pursuant to the authority of any applicable provisions of the United States Internal Revenue Code, as amended. The method of contribution provided for in this subsection shall be a privilege for the convenience of employees and no right of action shall accrue to the employee or any company designated to provide such optional retirement plan for errors, omissions, or decisions of any agent of the University System of Georgia regarding deductions under this subsection.

(d) All contributions authorized or required by this Code section shall be paid to the designated companies for the benefit of each participating employee by the financial officer of the employing institution.