市场最大“黑天鹅”：AI资本支出放缓，三大“巨雷”会是美股噩梦

Core Viewpoint - Barclays highlights that a slowdown in data center capital expenditure could pose a significant systemic risk to the U.S. stock market, particularly affecting the S&P 500 index's earnings and valuations [2][3]. Group 1: Risks Identified - The report identifies three major risks that could trigger a crisis: the potential overbuilding of computing facilities due to AI model efficiency improvements, physical limitations from power shortages, and financing pressures when capital expenditure growth exceeds cash flow generation [5][15]. Group 2: AI Investment Landscape - Despite a robust foundation for AI investments, the report notes that demand for computing power continues to outstrip supply, with a projected annual growth of 30% in capital expenditure [4]. - Approximately 10% of companies in the S&P 1500 index mentioned efficiency gains from AI in their earnings reports [4]. Group 3: Technical and Physical Risks - The rapid efficiency improvements of AI models may lead to overbuilding of existing computing facilities, reminiscent of the "dark fiber" situation during the dot-com bubble [6][9]. - The report warns that data centers are significant power consumers, with projections indicating that by 2028, their electricity usage could account for 12% of the total U.S. electricity consumption, nearly tripling from 2023 levels [13]. - The expansion of the power grid is unable to keep pace with demand, leading to rising electricity prices in certain regions, which could force data centers to slow down investments due to power availability issues [14]. Group 4: Financial Risks - Although tech giants' operating cash flow currently covers capital expenditures, the gap is narrowing, raising concerns about reliance on external financing if capital expenditures continue to exceed internal cash generation [16]. - The report estimates that AI-related investments contribute approximately 1 percentage point to the projected 1.4% GDP growth in the U.S. for the first half of 2025, indicating the critical role of AI investment in economic growth [19]. Group 5: Impact of Capital Expenditure Decline - A hypothetical 20% decline in data center capital expenditure over the next two years could lead to a 3-4% decline in S&P 500 earnings per share (EPS) and a 10-13% compression in valuations [21][22]. - Industries directly benefiting from AI infrastructure could see average price-to-earnings (P/E) ratio compressions of 15-20% [24].