深夜，中概股大跌！

Market Overview - US stock indices opened lower, with the Dow Jones down 0.02%, Nasdaq down 0.48%, and S&P 500 down 0.08% [1] Company-Specific News - UnitedHealth shares fell over 10% as the US Department of Justice investigates the company's medical insurance billing practices, with the company claiming it was unaware of the situation [3] - Alibaba's stock dropped nearly 8%, Beike fell 7%, and JD.com decreased by 4.5% [5] Economic Data - The US Producer Price Index (PPI) for April increased by 2.4% year-on-year, slightly below the expected 2.5%. The previous value was revised from an increase of 2.7% to 3.4%. Month-on-month, PPI decreased by 0.5%, against an expected increase of 0.2% [5] - Core PPI rose by 3.1% year-on-year, matching expectations, while the previous value was revised from 3.3% to 4.0%. Month-on-month, core PPI fell by 0.4%, compared to an expected increase of 0.3% [5] - Initial jobless claims for the week ending May 10 were reported at 229,000, in line with expectations, with the previous value revised from 228,000 to 229,000 [5] Federal Reserve Insights - Federal Reserve Chairman Jerome Powell indicated that future inflation may become more volatile, suggesting the US could be entering a period of more frequent and prolonged supply shocks, posing challenges for the economy and the central bank [5] - Powell mentioned that the Federal Reserve will reassess certain aspects of its strategic framework based on experiences from the past five years and will consider improving communication tools regarding uncertainty and risk [5]