US stocks fall as tech losses deepen weekly decline

US stocks closed lower Friday as declines in big technology companies weighed on the market, with the S&P 500 falling 1.1% and the Nasdaq dropping 2.1%, marking both indexes' worst week since June. Chipmakers led the losses amid deepening concerns about the longevity of the artificial intelligence investment boom, with Micron Technology falling 5.6% and Intel losing 5.8%. The Dow Jones Industrial Average fared better, slipping 0.3%, while European and Asian markets closed higher. For the week, the Nasdaq fell 4.5% and the S&P 500 dropped 1.9%, though the Dow gained 0.7%. Year-to-date, the S&P 500 remains up 11.9%, the Nasdaq up 12.5%, and the Dow up 8.2%.