
Japan’s Nikkei Stock Average had its worst day since 1987, falling 12.4% in a frenzy of selling triggered by disappointing economic data in the U.S. and a surge in the Japanese yen.
Other Asian markets also fell, with benchmark indexes in South Korea and Taiwan both down more than 8%. S&P 500 futures fell by more than 2% in Asia as U.S. markets prepared to open the week.