For a person who first becomes a member of the retirement system after August 31, 1996, the person's compensation for the purposes of the retirement system may not exceed the limit imposed by §401(a)(17) of the Internal Revenue Code of 1986 (26 USC §401(a)(17)), as adjusted by the commissioner of the internal revenue for cost of living increases in accordance with that provision. This limit does not apply to a person who first became a member of the retirement system before September 1, 1996.