S&P 500 Sheds $2.9 Trillion in Market Cap as AI Trade Unravels

The S&P 500 suffered its worst single-day loss since 2020, erasing an estimated $2.9 trillion in market capitalization—the largest one-day value destruction on record. The sell-off was driven by a sharp unwind in the artificial intelligence trade, as investors reassessed valuations for tech giants that had led the market higher. Key names like Nvidia, Microsoft, and other AI-focused companies saw steep declines, with the tech-heavy Nasdaq also plunging. The rout reflects growing concerns that AI-related spending may not deliver near-term profits, prompting a flight from high-multiple stocks. This reversal marks a stark shift from the AI euphoria that fueled much of 2023 and 2024's gains. For investors, the drawdown underscores the fragility of crowded trades and the risk of concentration in a handful of mega-cap stocks. The market's next move will likely hinge on upcoming earnings reports and any signals from the Federal Reserve. A sustained correction could force a broader re-rating of tech valuations, with implications for retirement accounts and institutional portfolios alike.