The 3.3 percent COLA that most federal retirees will receive starting with their January payments is down from the 4.1 percent they received at the start of this year, but still on the high side for recent adjustments. Since 1991, there have been only two increases that were larger—the 2006 COLA and a 3.5 percent COLA in 2001. The COLA, which was determined by a 12-month measuring period that ended with September inflation figures, worked out to be lower than earlier projections largely because of a relaxing of energy prices in September, which caused the inflation measure to drop by 0.6 percentage points during the month.