SEOUL, Oct. 30 (Yonhap) -- South Korean shares dropped by more than 3 percent Friday, drag... The Korean won strengthened against the U.S. The benchmark Korea Composite Stock Price Index (KOSPI) lost 206.92 points, or 3.48 percent, to close at 5,730.74, after falling as low as 5,599.42. After opening nearly 3 percent lower, the KOSPI extended its losses, prompting the Korea Exchange to activate a sell-side sidecar.