Only one in every three chief executives in South Korea has extended his or her term in office, with their average term period turning out to be shorter at large enterprises, data showed Wednesday. The number of senior management-level officials at top 500 local firms who have been reappointed at least once came to 188, or 36.4 percent, out of 516 respondents, according to the data compiled by local corporate information provider CEO Score. Chances for executives at larger firms to renew their three-year term turned out to be lower than those at smaller companies, the data showed. Less than 31 percent, or 69, of 227 executives in the top 30 firms renewed their three-year term as a C-suite member, with the corresponding figure coming in at 26 percent, or 39, of 150 officials at top 10 conglomerates. The average term for an executive at 500 firms was 3.1 years, with the figure for those working for top 30 companies coming in at 2.6 years. Hanjin Group, a leading shipping conglomerate, offered their executives the longest-serving period of 4.3 years on average, followed by Hyundai Department Store and LS Group. In contrast, Shinsegae, Daelim, Hyundai and two other major conglomerates have had no one who completed their three-year term. Of the top five conglomerates, Samsung had the lowest chance of reappointment, with only one in 30 executives finishing his or her term, the data showed.