刚刚！黑色星期五！原因找到了

Market Overview - On October 17, global markets experienced a significant downturn, with major indices in the US, Japan, and Europe all reporting declines [2][3][4] - The US stock futures continued to fall, with the Nasdaq 100 futures down 1.5%, S&P 500 futures down 1.4%, and Dow futures down 1% [2] - The Japanese Nikkei futures dropped approximately 2% after market close, while European markets opened with collective declines [3] A-share Market Performance - The A-share market opened lower and continued to decline throughout the day, with the Shanghai Composite Index down 1.95%, the Shenzhen Component down 3.04%, and the ChiNext Index down 3.36% [4] - Only 602 stocks rose, while 4,783 stocks fell, indicating a broad market sell-off [4][5] Hong Kong Market Performance - The Hang Seng Index fell by 2.5%, and the Hang Seng Tech Index dropped over 4% [6] Key Factors Behind the Decline - Concerns over a potential credit crisis were triggered by the significant drop in stock prices of two US regional banks, Zions Bancorp and Western Alliance Bancorp, due to fraudulent loans related to commercial mortgage-backed securities [6] - Zions Bancorp's stock plummeted 13% after announcing a $50 million loan write-off, while Western Alliance Bancorp's stock fell nearly 11% [6] - The KBW Bank Index recorded its largest decline in six months, with a total market value loss exceeding $100 billion across 74 large US banks [6] - Additional loan defaults, including the bankruptcy of Tricolor Holdings and First Brands Group, have raised further concerns about the stability of the credit market [7] - Market fears were compounded by potential setbacks in US-China trade relations, particularly with Micron's plans to halt the supply of server chips to data centers in China [7]