U.S. stocks eked out slight gains after a lower opening Monday, as a pair of U.S. non-manufacturing activity indices outweighed U.S. drug giant Pfizer Inc.'s falling first-quarter revenues. The blue-chip Dow Jones Industrial Average edged up 17.66 points, or 0.11 percent, to 16,530.55. The broader S&P 500 added 3. 52 points, or 0.19 percent, to 1,884.66. The Nasdaq Composite Index increased 14.16 points, or 0.34 percent, to 4,138.06. The market initially lost ground following disappointing earnings results released before the opening bell by the largest U. S. drugmaker Pfizer. Pfizer said that its revenues for the first quarter dropped 9 percent from a year ago to 11.35 billion U.S. dollars, missing market expectations. But the company reported adjusted earnings per diluted share of 57 cents for the first quarter, beating forecast of 55 cents. Shares of the Dow component dipped 2.57 percent to 29.96 dollars apiece. Weighing down the market sentiment, China's manufacturing activity continued to shrink in April, but at a slower pace. The HSBC/Markit China Purchasing Managers' Index stood at 48.1 in April, up from 48.0 in March, but modestly trailing analyst expectations. Shrugging off the investor pessimism, the U.S. stock market reversed earlier losses to close in green territory following encouraging U.S. services activity data. U.S. economic activity in the non-manufacturing sector continued to grow in April, with the index standing at 55.2, higher than March's reading of 53.1, according to the Institute for Supply Management. The number beat market expectations. Separately, a Markit report said that U.S. robust services activity growth continued in April, with the final seasonally- adjusted index registering 55.0 in April, down slightly from 55.3 in March. The number was modestly shy of market estimates. Wall Street kicked off May with a soft start, as investors mulled the old market adage of "sell in May and go away." But Analysts said that generally positive first-quarter earnings, the economy recovering from inclement weather conditions and the Federal Reserve's commitment to keeping rates low for a considerable time after asset purchases end still make stock markets profitable. Nevertheless, some traders still chose to stay on the sidelines, awaiting more clear evidence of the strengthening U.S. economy from the earning season coming to an end before placing big bets on stocks, which limited gains on Wall Street. Among other corporate news, shares of Target Corp. slipped 3.45 percent to 59.87 dollars apiece after the U.S. retailer announced Monday morning that its Chief Executive Officer and Chairman Gregg Steinhafel has stepped down. The leadership reshuffle came after a massive data breach during the 2013 holiday season. Last week, the three major stock indices logged weekly gains as investors cheered a stronger-than-expected U.S. non-farm payroll report in April. In other markets, the dollar fell marginally against major currencies Monday despite upbeat U.S. economic data. The dollar slipped to a two-week low versus the yen after disappointing data coming out from China boosted demand for safe- haven assets. In late New York trading, the euro rose to 1.3877 dollars from 1.3871 dollars of the previous session. The greenback bought 102. 12 Japanese yen, lower than 102.24 yen in the previous session. Oil prices fell as downbeat Chinese manufacturing data overshadowed the pair of generally positive U.S. non-manufacturing activity indices. Light, sweet crude for June delivery decreased 0.28 dollar to settle at 99.48 dollars a barrel on the New York Mercantile Exchange, while Brent crude for June delivery shed 0.92 dollar to close at 107.67 dollars a barrel. Gold futures on the COMEX division of the New York Mercantile Exchange rose to a three-week high on intensified tensions in Ukraine. The most active gold contract for June delivery rose 6.4 dollars, or 0.49 percent, to settle at 1,309.3 dollars per ounce.