According to Golden Finance, after Trump announced full tariffs, U.S. stocks fell by 10.5% in two trading days. Former U.S. Treasury Secretary Summers posted on X on Saturday that the S&P 500's performance for two consecutive trading days since World War II was worse than after Trump announced tariffs, only when the stock market crash in 1987 (26.4%), the 2008 financial crisis (12.4%) and the outbreak of the new crown epidemic (13.9%).