U.S. Stocks Tumble Again

After closing Monday at their lowest levels in more than a year, U.S. stocks saw another steep decline at the opening bell on Tuesday. The S&P 500 Index stumbled into a bear market, off 20 percent from its 2011 high. The Dow followed suit, falling almost 140 points at the start of trading. The Wall Street hit was foreshadowed by a sharp drop in markets around the world; global shares dipped to 15-month lows on Tuesday, spurred by renewed fears of a Greek default, which could trigger a second bailout package and possibly a double-dip recession.