Stock Market Today: S&P 500, Dow and Nasdaq all fall, put weekly gains in doubt; Treasury yields and oil prices rise MarketWatchTrading Day: Peace fog ReutersMarkets News, Aug. 11, 2026: U.S. Indexes End Lower for Second Straight Day; Oil Prices Extend Gains; CPI Report On Deck investopedia.comU.S. Stocks Fade for a Second Straight Session, Oil Rises WSJS&P 500 posts back-to-back losses, weighed down by tech sell-off and Iran uncertainty CNBC