Cars Become More Affordable in the U.S.

It took 23.1 weeks of American median family income to purchase and finance the average new passenger vehicle in the third quarter of this year compared with a revised 23.3 weeks in the second quarter, according to Comerica Bank's Auto Affordability Index.

The Dallas, Tex.-based bank reports that consumers spent $75 less per vehicle than in the previous three months. Comerica says declining interest rates also boosted affordability.

Sales volume in coming months will be sustained by easy access to relatively low-interest car loans and pent-up consumer demand for new vehicles, the bank predicts. It warns that the main threat to sales growth would be a federal balanced-budget crisis that sends the U.S. economy off the "fiscal cliff" in January.