Wall Street ends the week lower: S&P 500 falls 1.01% Friday, Nasdaq down 2.9% for the week

The main U.S. stock indexes closed lower on Friday, July 17, 2026, with all three finishing the week in the red. The S&P 500 fell 1.01% to 7,457.69, the Nasdaq Composite dropped 1.4% to 25,520.24, and the Dow Jones Industrial Average lost about 407 points (0.77%) to end at 52,146.42.

For the week, the S&P 500 shed roughly 1.6%, the Nasdaq 2.9%, and the Dow nearly 1%. The rout was led by a heavy sell-off in semiconductor stocks: the Philadelphia Semiconductor Index (SOX) entered bear-market territory and marked its worst week since the April 2025 tariff turmoil. The unveiling of a new AI model from Chinese startup Moonshot and a rotation out of richly priced tech names into economically sensitive shares added to the pressure.