The S&P 500 index rose 1.14% to 7,637.76 points on September 17, 2026, as the U.S. market rebounded following a FOMC rate hike. The rally was characterized by intense buybacks into semiconductor and AI stocks, contributing to a simultaneous breakout across major indices.
The Nasdaq composite also gained 1.1%, while the Dow Jones Industrial Average rose 0.61% to close at $51,778.04.
AI Demand and Tech Performance
The artificial intelligence boom has served as the primary driver for S&P 500 gains this year. Investors responded to positive signals regarding AI demand from major technology firms, including Palo Alto Networks and Dell Technologies.
Dell Technologies experienced the largest gain among S&P 500 stocks, jumping 15.8% after reporting strong second-quarter profits. The company raised its fiscal year revenue outlook and cited accelerating demand for AI computing. While Palo Alto Networks reported quarterly results that exceeded Wall Street expectations due to a strong market for AI cybersecurity, its shares fell 9.3% on Wednesday.
Market strategist Michael Antonelli of Baird noted that reports from companies like Dell reinforce the market’s perception of an AI spending tail wind.
Bond Yields and Macroeconomic Pressures
The market rebound followed a period of volatility and anxiety regarding government debt, rising prices, and the impact of global conflicts. Investors saw a reprieve as interest rate anxiety peaked and the 10-year Treasury yield fell to the 4.98% range, dropping below 5.0%.
Additionally, the rise in crude oil prices paused, with West Texas Intermediate (WTI) settling in the $101 range at $101.34 per barrel. This followed a period where oil prices surged due to the start of a U.S. war with Iran. The conflict intensified over a weekend when the U.S. attacked sites in Iran, leading to retaliatory strikes by Iran against sites around the Gulf region.
Despite these tensions, Brent crude settled at $95.63 per barrel and U.S. oil settled at $91.01 per barrel. In the energy sector, Chevron rose 0.3% after confirming plans to expand its operations in Venezuela.
Wall Street continues to expect the central bank to raise interest rates before the end of the year to combat inflation, which remains above 3%, while the Fed maintains a target goal of 2%.
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