Fed's Waller: 2022 rate hike possible, wants MBS taper first By Ann Saphir Reuters (Reuters) -A "very optimistic" Federal Reserve Governor Christopher Waller on Tuesday said the U.S. central bank may need to start dialing down its massive asset purchase program as soon as this year to allow the option of raising interest rates by late next year. "The unemployment rate would have to drop fairly substantially, or inflation would have to really continue at a very high rate, before we would take seriously a rate hike in 2022, but I'm not ruling it out," Waller told Bloomberg TV in his first public comments since the Fed met earlier this month.