April 19, 2013 at 4:20 PM ET
Stocks reversed a two-day slump Friday, with the S&P 500 rebounding after finishing below its 50-day moving average for the first time this year, but all three major averages still logged their worst weekly drop this year.
The Dow Jones Industrial Average eked out a gain, after falling nearly 100 points at the open. IBM and GE led the laggards, while Microsoft and American Express were among the best performers. IBM's sharp decline single-handedly put more than 100 points of downward pressure on the blue-chip index.
Among key S&P sectors, consumer staples rallied, while techs finished in the red.
"Volume's been light—there's no real economic news, nothing out of Washington, Fed's quiet and no more real earnings until Monday," said Alan Valdes, director of floor operations at DME Securities. "Most people are watching what's happening in Boston, although it's not really moving the markets."
The two suspects in the Boston Marathon bombing killed an MIT police officer and hurled explosives at police in a car chase and gun battle overnight that left one of them dead and his brother on the loose. Thousands of officers swarmed the streets in a manhunt that all but paralyzed the Boston area. Residents in the Boston area have been told to stay inside while police search for the suspect.
Watch Live Now: Boston Police Search for Suspect
With no major economic news on tap Friday, the focus is expected to remain largely on corporate earnings.
McDonald's edged lower after the fast-food chain missed earnings expectations by a penny and said global comparable sales were down 1 percent for the quarter, with China and Japan weakness helping drive sales in the Asia/Pacific, Middle East, and Africa (APMEA) region down 3.3 percent.
IBM tumbled sharply after the computer hardware and software company posted quarterly results that fell short of consensus estimates and issued a full-year earnings forecast below estimates. In addition, the tech firm said it will accelerate the pace of job cuts after sales of software and mainframe computers slowed.
Also among techs, Microsoft gained after the software giant topped earnings expectations. Separately, the company announced that CFO Peter Klein will leave in June. And Google easily beat earnings estimates, while revenue fell slightly short of forecasts.
Chipotle Mexican Grill surged to lead the S&P 500 gainers after the fast-casual restaurant chain posted a jump in quarterly earnings.
To date, 104 S&P 500 companies have reported results this quarter with 67 percent of firm topping earnings expectations. Meanwhile, only 43 percent have exceeded revenue estimates.
"Earnings, I would argue are coming in better than expected. Underneath the surface is something that's not quite so healthy.They're struggling on the top line, the revenue side. That is indicative of a global economy growing below trend," said Bill Stone, chief investment strategist at PNC Wealth Management.
SeaWorldrallied in its market debut on the New York Stock Exchange after the company priced its IPO at $27 per share on Thursday, at the high end of its expected range.
Read More: SeaWorld IPO Hopes to Make a Splash
Apple slumped to close near $390 a share, breaking below $400 for the first time since December 2011 earlier this week. Apple tumbled 9 percent this week alone and has erased more than 40 percent since hitting its all-time high of $705 a share in September, The iPhone maker also lost its title of the world's most valuable company by market cap to oil giant ExxonMobil on Wednesday.
Read More: Wall Street Turns Viciously Against Apple
Vertex Pharmaceuticals skyrocketed after the drugmaker reported a successful trial for its experimental cystic fibrosis drug.
Meanwhile, GlaxoSmithKline traded lower after the pharmaceutical giant was accused of market abuse by the U.K.'s Office of Fair Trading on Friday. The regulator alleged that Glaxo paid generic firms to delay launching cheap copies of its top-selling anti-depressant Seroxat.
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