US personal spending was flat in the key December holiday shopping season, despite a rise in incomes, government data showed Monday. Personal spending was unchanged after rising 0.1 percent in November, the Commerce Department said. Americans kept their wallets shut and bolstered savings as their incomes rose a solid 0.5 percent in December, accelerating from the 0.1 percent rise the month before. The data surprised analysts, who on average forecast a 0.1 percent rise in spending, income. Adjusted for inflation, disposable income rose 0.3 percent after slipping less than 0.1 percent in November. The personal saving -- the amount of disposable income not spent -- rose to 4.0 percent from 3.5 percent in November.