Sales of new single-family houses shot up at the tail of the spring buying season, shrinking the months' supply of new homes on the market, data released today by the U.S. Census Bureau shows. New-home sales jumped 18.6 percent from April to May, to a seasonally adjusted annual rate of 504,000. That's a 16.9 percent increase in the pace of sales from the same time a year ago. On the one hand, the pace of new-home sales in May was the strongest in six years, noted Bill McBride, author of the blog Calculated Risk. On the other hand, sales were still only slightly better than the bottoms seen during previous recessions. Source: CalculatedRiskBlog.com. The number of new homes for sale stayed flat from April to May, at 189,000, but that's up 16.7 percent from last year. At the c...