U.S. stock markets gave up their winning ways today, trading lower after logging gains for the past four consecutive sessions. For the day, the Dow Jones Industrial Average (INDEX: ^DJI) shed 40 points to end 0.3% lower. The other two major U.S. stock indexes also fell, with the S&P 500 and the Nasdaq losing 0.3% and 0.2%, respectively. In the absence of any major macro news event, the market's often-cited "fear gauge," the VIX (INDEX: ^VIX), also shed 1.2%. However, individual stocks still provided plenty of movement for investors to digest.

Around the markets
In keeping with tradition, shares of IPO bust Groupon (Nasdaq: GRPN) lost another 9.8%, as survey data from 115 local merchants painted its daily-deal service in an unfavorable light. The data revealed that while merchants who used Groupon did experience an increase in customer volume, those same customers also tend to spend less and return less often than typical customers. Merchants who used the site reported a 53% satisfaction rating, though only 4% reported their experience as "highly profitable." Groupon's stock hasn't been especially profitable for investors, either, since it listed its shares last November. Its stock now sits a brutal 82% lower than its IPO price.

On the upside, Tesla Motors (Nasdaq: TSLA) surged 7.1% as Morgan Stanley raised its rating of the electric-car upstart to an overweight rating. As the company prepares to accelerate the release of its next-gen Model S to market, investors have expressed frustrations over the product's seemingly slow ramp-up. However, the company has considerable capacity that should allow it to increase shipments from an estimated 230 this quarter to an expected 15,000 in 2013.

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