Asian markets tumbled following Wall Street’s worst day since early August, driven by disappointing US data and declining oil prices, raising concerns about global economic health. The Nikkei 225 led the downturn, dropping over 3%, with losses also seen in Australia and South Korea. The S&P 500 and Nasdaq 100 suffered their worst September starts since 2015 and 2002, respectively, amid fears of a recession. A tech stock selloff, particularly Nvidia’s 9.5% plunge, further stoked investor anxiety.