DreamWorks Animation's stock troubles continued this week as Goldman Sachs downgraded the company's stock to sell based on weak ticket sales for Puss in Boots and soft DVD and Blu-ray sales for Kung Fu Panda 2. The stock has rebounded from a low point of $16.50 in late December, and closed Thursday at $17.89. Still, the stock is down significantly in the past year and prospects for a change are uncertain. Goldman Sachs analyst Drew Borst reported sales of Kung Fu Panda 2 were well below expectations at 4.5 million units worldwide in the fourth quarter. Borst set a target price for the company's stock at $15. He also said the domestic gross for Puss in Boots ' first 10 weeks of release was 15 percent below Goldman's estimate of $180 million at about $147 million.