If you're looking for signs that the used car market is getting easier for dealers, CarMax Inc. (KMX) just delivered some disappointing news. The company's November data from its CarMax Auto Finance (CAF) securitization portfolio shows credit trends that remain stubbornly soft, and in some areas, are deteriorating faster than usual.

The Numbers Behind the Concern

Wedbush analyst Scott Devitt broke down the latest figures in a note to clients, maintaining his Neutral rating and $40 price target on the stock. November, he notes, typically brings weaker trends compared to October and September—it's just how the calendar works in auto finance. But this November brought some numbers that stand out, and not in a good way.

Delinquency rates ticked up sequentially, which is pretty much on schedule with historical patterns. Devitt estimates the portfolio-level delinquency rate climbed 19 basis points month-over-month, right in line with the seasonal average. So far, so predictable.

Here's where it gets interesting: the cumulative net loss rate jumped 7 basis points, more than double the seasonal average of 3 basis points. That's a meaningful divergence, and it suggests that more loans aren't just going delinquent—they're actually defaulting.

What Management is Saying

"Results thus far are trending in line with management commentary, in our view, which suggests that delinquencies will continue to ramp through the rest of the year, before improving again during the tax refund period," Devitt wrote.

Translation: expect things to keep getting worse before they get better, with some relief potentially arriving when tax refunds hit consumer bank accounts early next year.

Investor Anxiety Rising

The bigger picture here isn't just about one month of data. According to Devitt, investors are increasingly concerned about "the company's credit exposure, and more broadly, management's ability to sustain market leadership." When your financing arm starts showing cracks, it raises questions about the entire business model, especially in a competitive used car market.

CarMax shares were up 0.87% at $40.98 at the time of publication on Wednesday. Investors looking for exposure to the company can access it through ETFs like iShares S&P SmallCap 600 Value ETF (IJS), Vanguard S&P Small Cap 600 Value ETF (VIOV), and SPDR S&P Retail ETF (XRT).