South Korean and Japanese equities closed lower on Aug. 18, according to Bitget market data. The KOSPI, South Korea's main stock index, fell 1.55% to 6869.80. Samsung Electronics lost 2.19%, while SK Hynix gained 1.03%. In Japan, the Nikkei 225, a benchmark index of major listed companies, dropped 2.54% to 67460.73.