This fourth proposed Constitutional Amendment sets a limit of eighteen years for an individual to serve in the US Congress.
#4 - PROPOSED AMENDMENT to the US CONSTITUTION on CONGRESSIONAL TERM LIMITS
Section 1. No individual shall serve more than a total of eighteen years as a member of the United States Congress.
Section 2. At the time this amendment is ratified members of the United States Congress may serve out their current term of office if they have served eighteen years or longer, but not beyond.
Section 3. No individual shall be elected to Congress if their next term of office would take them beyond the eighteen years of service limit.
Section 4. This article shall be inoperative unless it shall have been ratified as an amendment to the Constitution by the legislatures of three-fourths of the several states within seven years from the date of its submission according to Article V of the United States Constitution.