Investors prepared for another week of developments on President Trump's fast-moving tariff policies and for the kickoff of Big Tech earnings reports.

At the close, the blue chip Dow Jones Industrial Average was down 2.5% at 38,170, the broader S&P 500 was off 2.4% at 5,158, and the tech-heavy Nasdaq Composite was 2.6% lower at 15,870. Big drops for several mega-cap stocks created notable pressure,