Summary Box: Industrial production rises in Dec.

FACTORIES ARE BUSIER: Activity at the nation's factories, mines and utilities rose 0.8 percent in December, the largest increase in five months. Industrial production increased every month last year except for one.

GOOD MOMENTUM: Rising production at industrial companies gives the economy solid momentum heading into the new year. Economists predict the economy will grow more strongly this year and that companies will slowly boost hiring.

STRONGER DEMAND: Americans are spending more, and people in other countries are buying more U.S.-made goods shipped overseas. That's boosting factory production.