WESTLAKE VILLAGE, Calif. — The market penetration of long-term financing deals reached a record level last month, according to J.D. Power and Associates, which found that 30.1 percent of retail sales in March included 72-month (or longer) loan terms.

J.D. Power's Thomas King told SubPrime Auto Finance News' sister publication Auto Remarketing earlier this week that "it's the highest level we've observed."

The 72-plus-month financing penetration rate observed in March was up from 28.3 percent in February and 24.6 percent in March 2011.

King explained that weaker-credit customers returning to market played a role in this increase, but it wasn't the only driver.

"High long-term financing penetration in the industry is due in part to customers with lower credit returning to market," King said, noting that "customers with lower credit scores have a higher propensity to use longer loans than buyers with higher credit scores.

"However, the rise in long-term financing also reflects increased availability of such loans — both from OEMs and from third-party lenders now that credit restrictions have eased — and also the need to offset the higher transaction prices the industry is earning as a result of better aligned supply and demand," he continued, pointing out that these long-term financing deals can serve as a "convenient" means to slice monthly payments.

So how rapidly are weaker-credit customers returning to the market?

According to King, there was a 22.9 percent year-over-year uptick in sales to consumers whose FICO scores were less than 649. (Meanwhile, there was a 7.4-percent uptick in sales to buyers with FICO scores higher than 720.)

This increase for the lower-credit buyer spectrum, however, comes with a caveat.

"It's important to note that while sales to lower credit buyers are growing strongly, they are doing so following a very significant decline during the recession. As such, the recovery in this portion of the market can be viewed as a reversion to more typical levels rather than unprecedented growth," King explained.

"The drivers of the growth are a generally improved economic environment and the removal of some of the most severe lending restrictions that impacted this buyer group disproportionately — such as limited access to 72-month loans and reduced maximum loan-to-value ratios," he added.