U.S. stocks surged on Thursday, lifting the Dow industrials back into positive terrain for the year, as heavy-equipment maker Caterpillar boosted its profit outlook and an unexpected increase in euro-zone manufacturing eased worries about the global economy.
But equities pared gains in late trading as New York City's Bellevue Hospital said it was testing a doctor who recently returned from West Africa for Ebola after he exhibited some symptoms consistent with the virus. He was the latest of many patients to have been tested for Ebola-like symptoms in the city in recent weeks; all of the prior tests were negative.
"You would think that if Nigeria could contain it, then so could we, but this is a very manic-depressive market that we're in," said Peter Boockvar, chief market analyst at the Lindsey Group, who instead offered the view that the market retreated after the S&P 500 hit technical resistance at its 100-day moving average of 1,961.50.
"I guess we rolled over during it. I don't know why we were up 35 points to begin with," said Boockvar.
Investors fled perceived safe-havens including U.S. Treasury notes and gold, buying assets viewed as riskier as corporate earnings and projections for the future, especially from multinationals, eased worries about the global economy.
Caterpillar rallied after reporting a quarterly profit that soared past estimates; 3M jumped after the diversified manufacturer posted higher quarterly profit, and General Motors also tallied a better-than-expected profit in the third quarter.
"It's earnings. When we started the day the Dow was still down on the year, then you saw Caterpillar and GM come out with good news," said Chris Gaffney, senior market strategist, Everbank Wealth Management, referring to the Dow's return to the black for 2014.
The volatility of last week could be interpreted as a sign that investors are worried about whether the U.S. economy can stand on its own, once the Federal Reserve pulls the plug on bond purchases, otherwise known as quantitative easing, said Gaffney. "This week, these earnings show perhaps it will."
On Thursday, the CBOE Volatility Index, a measure of investor uncertainty, fell 7.5 percent to 16.53.
Thursday's economic reports had the four-week average of Americans filing for jobless benefits dropping to a 14-year low.
The Conference Board's index of leading indicators for September increased 0.8 percent.
Surveys had euro-area businesses performing far better than expected in October, along with a slight expansion in China's manufacturing sector.