Encouraging signs out of Europe and a surprisingly strong report on the US housing market drove the Dow Jones industrial average up more than 330 points today. It was the best day for stocks this month. The Spanish government pulled off a successful debt auction, and gauges of business and consumer confidence in Germany rose unexpectedly. The Commerce Department, meanwhile, said builders broke ground on 685,000 new homes last month, a 9.3% jump from October. That's the highest level since April 2010.