The National Assembly of The Republic of Korea, a State Owned entity headquartered in South Korea, is a unicameral legislature operating with approximately 320 employees. The assembly's term is four years, and it functions as a body consisting of at least 200 members. Its structure includes single-member constituencies, which comprise 246 seats, while 54 seats are allocated by proportional representation. Historically, in 1990, the assembly held 299 seats, with 224 directly elected from single-member districts in the April 1988 general elections, and the remaining seventy-five representatives appointed by political parties based on a proportional formula. The latest legislative elections were held on 11 April 2012. Candidates for election to the assembly must be at least thirty years of age. Under the Sixth Republic, the assembly cannot be dissolved by the president, a change from the more authoritarian Fourth Republic and Fifth Republic periods (1972–80 and 1980–87, respectively).