U.S. stocks reversed gains, sending the Standard & Poor’s 500 Index toward its longest decline since November, as reports showed consumer confidence trailed economists’ projections and business activity cooled.

Stocks erased gains as reports showed that consumer confidence unexpectedly dropped in January and a gauge of business activity fell, underscoring forecasts that the U.S. economy will cool after expanding at the fastest pace since the second quarter 2010. Earlier gains were triggered after most countries in Europe agreed to tighter budget controls and Greece made progress on debt talks.

Dow 12,607.44 -46.28 -0.37%, Nasdaq 2,807.60 -4.34 -0.15%, S&P 500 1,310.40 -2.61 -0.20%

Exxon Mobil dropped 2.1 percent to $83.66. Revenue rose 16 percent to $121.6 billion during the quarter, less than the $124.4 billion average of five analysts’ estimates compiled by Bloomberg.

UPS lost 1.1 percent to $75.34. The company reported sales of $14.17 billion, missing the average analyst estimate in a Bloomberg survey of $14.45 billion.

ADM sank 5 percent to $28.24. The company, led by Chairman and Chief Executive Officer Patricia Woertz, has missed analysts’ estimates for three straight quarters. Operating profit at the agricultural-services unit, the company’s largest segment by revenue in fiscal 2011, fell 63 percent to $158 million after U.S. grain exports declined because of a smaller domestic crop and “adequate” global supplies, ADM said.

RadioShack Corp. tumbled 30 percent to $7.18 after the consumer-electronics retailer suspended share repurchases and reported preliminary fourth-quarter earnings that trailed analysts’ estimates.