美股三大指数集体收跌，大型科技股多数走低，中概股涨跌不一

Market Overview - The US stock market experienced a collective decline on August 5, with the Dow Jones down 0.14% to 44,111.74 points, the S&P 500 down 0.49% to 6,299.19 points, and the Nasdaq Composite down 0.65% to 20,916.55 points [1][2]. Economic Indicators - The ISM reported that the US services PMI for July was 50.1, below market expectations of 51.5 and the previous month's 50.8, indicating near stagnation in service sector growth [2][3]. - Employment indicators fell from 47.2 to 46.4, marking a low point since the COVID-19 pandemic [2]. - The prices for materials and services rose to 69.9, the highest since October 2022 [2]. Policy and Regulatory Environment - The report highlighted challenges for the Federal Reserve, as rising price indices contrast with weakening activity and employment metrics [3]. - New tariff announcements from former President Trump, including a "small tariff" on imported drugs that could rise to 250%, are expected to impact market sentiment [3]. Company Performance - Major tech stocks mostly declined, with Nvidia down 0.97%, Microsoft down 1.47%, and Meta down 1.66%. Amazon was an exception, rising by 0.99% [4][5]. - Palantir's stock surged by 7.85%, reaching a market cap exceeding $400 billion, following a quarterly revenue report that surpassed $1 billion, a 48% year-over-year increase [5]. Chinese Stocks - The Nasdaq Golden Dragon China Index fell by 0.56%, with mixed performances among popular Chinese stocks [7]. Company News - OpenAI, Google, and Anthropic have been approved as AI suppliers for the US government, which is expected to accelerate the adoption of AI tools in federal operations [8][9]. - Coinbase announced plans to issue $2 billion in convertible bonds to raise funds for stock buybacks and debt repayment [10]. - AMD reported a second-quarter net profit of $781 million, a 31% year-over-year decline, with revenues of $7.69 billion, a 32% increase [11]. - Supermicro's fourth-quarter net sales were $5.76 billion, below analyst expectations, with a projected fiscal year 2026 net sales of at least $33 billion [12]. - Lucid reported a second-quarter adjusted loss of $632.1 million, with revenues of $259.4 million, a 29% increase year-over-year [13].