U.S. stocks ended lower on Monday as the CNN Money Fear and Greed Index fell to 31 from 33, remaining in the Fear zone. The Dow Jones Industrial Average dropped about 152 points to 52,421.20, while the S&P 500 fell 0.48% to 7,619.98 and the Nasdaq Composite declined 0.56% to 26,186.41. Oil prices surged after Saudi Arabia shut the East-West pipeline, while the 10-year Treasury yield briefly exceeded 5% for the first time since 2023 on an intraday basis. Investors shifted out of AI hardware and into security software after frontier-lab chief executives spent the weekend debating the pace of model development. Zscaler climbed about 17%, while Corning fell 14% after announcing a $2 billion offering. The Fear and Greed Index measures market sentiment through seven equally weighted indicators on a scale from 0 to 100, with 0 representing maximum fear and 100 maximum greed. Investors were also awaiting earnings from Forgent Power Solutions, Vera Bradley and Trip.com Group.