South Korean stocks closed almost unchanged Thursday as investors took to the sidelines, cautious about buying shares amid a dearth of major market momentum, analysts said. The local currency remained flat against the U.S. dollar. The country's key stock index, the KOSPI, slipped 2.29 points, or 0.11 percent, to finish at 1,999.30. Trading volume was light at 215 million shares worth 3.16 trillion won (US$2.98 billion) with gainers outpacing decliners 405 to 394.