A. The collection of members' contributions shall be as follows:
(1) Each employer shall cause to be deducted on each and every payroll of a member eight percent of the earnable compensation of such member; provided, however, that in the event the employer's contribution to the retirement system as approved, funded, and appropriated by the legislature is less than eleven and eight-tenths percent of the total earnable compensation of each member, each employer shall cause to be deducted on each and every payroll of a member seven percent of the earnable compensation of such member.
(2) The treasurer of each employer shall make the deduction provided above and shall transmit on or before the tenth day of each month to the secretary-treasurer of the board of trustees the sum of such deductions made during the preceding month.
B. Nothing in this Section shall prevent the board of trustees from modifying the method of collecting the contributions of members in the employ of employers other than parish or city school boards.