South Korean stocks opened lower on Friday ahead of earning reports by major listed companies and concerns that the Chinese economy may be slowing down, analyst said. The benchmark Korea Composite Stock Price Index (KOSPI) lost more ground after opening in the negative territory and was down 9.65 points, or 0.50 percent, to 1,937.94 in the first 15 minutes of trading. Analysts said institution and foreign investors were off-loading more shares than they buying, putting pressure on the bourse.