U.S. stocks tumbled, with the Dow Jones Industrial Average poised for its worst day since October, as a drop in durable-goods orders and disappointing results from Caterpillar Inc. to Microsoft Corp. heightened concern about the economy™s strength.

Technology shares in the Standard & Poor™s 500 Index had the biggest drop in more than three year. Microsoft lost 9 percent as software-license sales to businesses were below forecasts. Caterpillar plunged 7.5 percent after forecasting 2015 results that trailed estimates as plunging oil prices signal lower demand from energy companies. DuPont Co. dropped 2.8 percent as a stronger dollar cuts into the chemical maker™s profit. Procter & Gamble Co. and United Technologies Corp. declined at least 1.3 percent after saying the surging greenback will lower full-year earnings.

The Standard & Poor™s 500 Index slipped 1.4 percent to 2,027.78 at 12:15 p.m. in New York, below its average price for the past 50 days. The Dow declined 347.17 points, or 2 percent, to 17,331.53, poised for the biggest drop on a closing basis since October.

Trading in S&P 500 companies was 23 percent above the 30-day average for this time of the day as exchanges opened for a full day despite a snow storm that shut down travel around New York City overnight and during part of the morning.

Source : Bloomberg