DALLAS — The purchase and financing of an average-priced new vehicle accounted for 23.2 weeks of median family income in the fourth quarter, an improvement of 0.5 weeks, according to Comerica Bank.

Consumers spent an average of $700 less, down 3 percent, on a new car in the fourth quarter. Meanwhile, the cost of financing a new car climbed due to the average interest rate climbing by 0.5 percent.

However, the financial institution noted that the third-quarter reading was revised downward 0.1 weeks to 23.7 weeks of median family income.

"Consumers continued to opt for less expensive cars in the fourth quarter, even as auto loan rates rose and the national recovery gradually reaccelerated," explained Dana Johnson, Comerica chief economist.

"The average interest rates on auto loans rose 4.6 percent, the highest since the first quarter of 2009. Looking ahead, affordability could erode as the cost of financing a new car increases due to rising interest rates," Johnson continued.