"When you have a housing recovery, it's nearly impossible for the U.S. economy to slip into recession," Zentner says.â¿¿ MANUFACTURING Factories appear to be recovering slowly from a slump last fall. The Institute for Supply Management's index of manufacturing activity rose last month from November. And a measure of employment suggested that manufacturers stepped up hiring in December. Factories had cut jobs in three of the four months through November, according to government data. Another encouraging sign: Americans are expected to buy more cars this year. That would help boost manufacturing output. Auto sales will likely rise nearly 7 percent in 2013 over last year to 15.3 million, according to the Polk research firm. Sales likely reached 14.5 million last year, the best since 2007. In 2009, sales were just 10.4 million, the fewest in more than 30 years. And if Congress can raise the federal borrowing limit without a fight that damages confidence, companies might boost spending on computers, industrial machinery and other equipment in the second half of 2013, economists say. That would help keep factories busy.