Closing Bell: Weight Watchers Gains on Oprah Ad; Stocks Slip

It's the second-last day of trading for the year and stocks appeared determined to close just where they started. Stocks gave back most of the week's earlier gains on global growth concerns, putting the S&P 500 just a fraction higher than where it began 2015. Weight Watchers (WTW) surged as the company's first commercial featuring media mogul Oprah Winfrey began to air. Earlier this year, Winfrey took a 10 percent stake in the company. Since then, shares have rocketed more than 200 percent higher. Tesla (TSLA) climbed on a bullish note from analysts. Global Equities Research analysts said they were optimistic that the automaker can deliver vehicles in the fourth quarter at the upper end of its previous guidance. TheStreet's Keris Lahiff reports from New York.