Why South Korea’s KOSPI Jumped More Than 2%｜Oil, U.S. Yields and Chip Stocks
South Korea’s KOSPI jumped more than 2% on September 18, 2026, as lower oil prices, easing U.S. Treasury yields and a rebound in technology stocks brought investors back into risk assets. The rally was part of a broader recovery across Asia, but South Korea moved more sharply as Samsung Electronics and SK Hynix strengthened and foreign investors returned to net buying. For global investors, the day’s move is easier to understand by looking at three markets together: oil, U.S. bonds and semiconductors. Contents KOSPI Jumps as Asian Markets Recover Wall Street’s Tech Rebound Reaches Seoul Oil and U.S. Treasury Yields Ease Pressure What to Watch Next KOSPI Jumps as Asian Markets Recover Asian stocks moved higher on September 18 after several difficult sessions dominated by expensive oil, inflation concerns and rising global interest rates. South Korea stood out. The KOSPI climbed more than 2%, while the broader MSCI Asia-Pacific index outside Japan gained around 1...