The extra yield Treasury investors demand to hold 10-year notes instead of 2-year securities touched the highest level in more than a month on evidence the threat of deflation is waning. The 30-year bond yield was headed for a fourth weekly gain in the longest stretch of advances since May 2009 before a government report forecast to show U.S. consumer prices increased for a second month. “Investors got very pessimistic at the end of August, and they have sort of corrected that pessimism” about the U.S. economic outlook, said Luca Cazzulani, a senior fixed-income strategist at UniCredit SpA in Milan.