U.S. stocks posted slight gains Wednesday, the first trading day of 2019, recovering from sharp losses early in the session. Wall Street concluded 2018 trading on Monday, with the three major stock indexes posting their worst annual performance since the 2008 financial crisis. The Dow Jones industrial average rose 18.78, or 0.1 percent, to 23,346.24. The broader Standard & Poor's 500 index rose 3.18, or 0.1 percent, to 2,510.03. The technology-heavy Nasdaq composite index rose 30.66, or 0.5 percent, to 6,665.94.