The Commerce Department said that housing starts jumped 20.2 percent to an annual rate of 1.14 million homes, the fastest clip since November 2007. "The housing market comes back in the spring, is what realtors always say, and boy is this true today," said Christopher Rupkey, chief financial economist at MUFG Union Bank, in a note to clients. Before the market opened, Wal-Mart Stores turned in sluggish sales and a drop in quarterly earnings as raises for workers and a rising dollar put pressure on its profits. Take-Two Interactive, which makes the "Grand Theft Auto" video games, surged 15 percent after reporting earnings that were sharply higher than analysts had expected. Investors were cheered by an ECB official's remark that the central bank would step up its bond-buying stimulus program in May and June in anticipation of slow trading in July and August. Greece was also in focus after its finance minister said he expects an agreement with bailout creditors within the next week, potentially saving the cash-strapped country from defaulting on its debts.