(AP) MAJOR PULLBACK: Stocks had their worst day since August on Thursday as traders worried that the Federal Reserve could cut back on its economic stimulus. Concerns that the market, which has hit 33rd record highs this year, had come too far, too fast also weighed on investors' minds.
TWITTER'S BIG DAY: Twitter shares soared 73 percent on their first day of trading to close at $44.90. The company priced its shares at $26 the night before. With today's surge, the micro-blogging technology company is valued at $31 billion.
THE NUMBERS: The Standard & Poor's 500 index fell 23.34 points, 1.3 percent, to 1,747.15. The Dow Jones industrial average lost 152.90 points, or 1 percent, to close at 15,593.98. The Nasdaq composite lost 74.61 points, or 1.9 percent, to 3,857.33.