S&P 500 ends higher as strong inflation data cements rate-hike bets

September 11 saw Wall Street finish higher as oil prices dropped and robust consumer price data supported the notion that the Federal Reserve would hike interest rates next week to curb inflation. Technology firm Dell surged 12% to a record high, while Hewlett Packard Enterprise and HP both climbed 12% and 8.4%, respectively, following Oracle's quarterly earnings that beat expectations.

Oracle, however, slipped 1.8%. Data revealed that US consumer prices surged in August, driven by a rebound in gasoline costs following two months of declines, heightening pressure on the Fed to tighten monetary policy. Interest rate futures now indicate a near 90% probability of a rate increase at the September 16 policy meeting, according to the CME FedWatch tool, a significant uptick from 72% on September 10.

Thomas Martin, a senior portfolio manager at GLOBALT Investments, remarked, "That’s pretty much as close to a slam dunk as you’re going to get." With the Fed likely to act, Martin believes the move would be beneficial in keeping inflation under control. The S&P 500 rose 0.86% to close at 7,656.98 points; the Nasdaq gained 0.96% to 26,333.04 points, and the Dow Jones Industrial Average increased 0.98% to 52,573.29 points.

Nine of the 11 S&P 500 sector indexes rose, led by communication services (up 1.35%) and consumer discretionary (up 1.13%). Trading volume on U.S. exchanges was lighter than usual, with 14 billion shares exchanged, compared to the average of 14.9 billion shares over the previous 20 sessions. The CBOE Volatility Index, Wall Street's fear gauge, slipped 2 points to 15.88.

The S&P 500's rally comes after recent market unease over inflation, rising long-term Treasury yields, and worries about substantial spending on AI data centers. The S&P 500 has fallen roughly 2% from its August 13 record high and is up 12% for the year. During the week, the S&P 500 fell 0.8%, and the Nasdaq declined 0.7%. The S&P 500's recent setback, combined with strong earnings expectations, has brought the index to a 19-times-expected-earnings valuation, the lowest since April 2025, a period marked by President Donald Trump's "Liberation Day" tariff announcements causing global markets to tumble.

Oil prices declined but stayed around a 9% increase for the week due to Middle East shipping route attacks fueling concerns about persistent supply disruptions. For the S&P 500, eight new highs and nine new lows were recorded; the Nasdaq reported 45 new highs and 182 new lows.