The Daily Digit is 2.6%. Personal income for Americans was up 2.6% in December, according to the U.S. Commerce Department . That was the biggest increase since 2004 and well above analysts' expectations. But it may be just a one-time deal. The Commerce Department said personal income rose because of special dividends and accelerated bonuses to beat increases in taxes this year. Exclude the one-time factors, and after-tax income rose 0.4%.