As of June 30, 2016, the total U.S. household debt amounts to over $12 trillion. One of the largest concerns of the next debt bubble is the student loan debt market, which has grown to over $1 trillion. However, there are some debt markets ballooning and are going unnoticed by many.

The 2016 U.S. auto loansindustry is reminiscent to that of the subprime mortgage loan industry that sparked the global financial crisis between 2007 and 2009. The auto loan debt industry has been growing at an average annual rate of nearly 10%. U.S. auto loan debt was just above $700 billion on June 30, 2010, but grew to $1.103 trillion as of June 30, 2016. This has bolstered U.S. auto sales and allowed many auto companies to recover their losses during the U.S. recession, which has been great for the overall economy.

Americans have been borrowing at a record pace for vehicles, based on June 2016 data provided by Experian. Moreover, they have been making record larger monthly payments and extending their auto loans. The average auto loan comes in at $30,032, the first time in history that the average amount borrowed to purchase a new vehicle topped $30,000. Additionally, the average monthly payment topped $503, the first time in history.

The average term for the auto loans is 68 months, nearly 6 years. This was the longest average auto loan term that was ever noted by Experian. With auto loans at such a high average level, consumers have been stretching out their auto loans, which lower the average monthly payment. Consequently, investors should be concerned about whether the U.S. auto loan debt market will burst.

According to Fitch ratings, for the month of July, delinquencies of at least 60 days for subprime auto loans were up 13% month over month. Additionally, delinquencies of at least 60 days are 17% higher when compared to the same period last year.

The CEO of JPMorgan Chase, Jamie Dimon, stated that the auto loan debts are a little stretched and believes that someone is going to get hurt.

There are more consumers defaulting on subprime auto loans. Subprime auto loans are intended for people with a FICO score of 600 or less, and those who qualified for this type of loan and are 60 days or greater behind on payments reached 4.59% in July. However, delinquencies of at least 60 days of prime auto loan borrowers remained at 0.4%, which was still 21% higher than last year.

The annualized net loss rate rose above 7%, which was a 28% from the same period last year. Similar to the mortgages that were packaged in credit default swaps (CDS) and credit default obligations (CDO), U.S. auto loans are packaged and sold to investors.

Santander Consumer USA Holdings (NYSE: SC) is primarily focused on auto loans and is down 42.47% over the past year and over 20% year to date as of September 1, 2016. Santander Consumer USA Holdings is the U.S. auto-lending division of Banco Santander, and it has come under fire for its delay of its second-quarter earnings report.

Banco Santander and auditors evaluated how Santander Consumer accretes its loan discounts, which could affect its stock price further. During the first quarter of 2016, Santander Consumer’s delinquency ratio and individually acquired installment contracts net charge-off ratio increased to 3.1% and 8.2%, respectively. Consequently, investors may want to watch out for other U.S. auto lenders.

We’ve seen a sharp increase in delinquencies of 60 days or more during the month of July. This may show signs of the U.S. auto loan debt market ballooning. Investors should continue to watch for this industry and whether it will affect the overall market. Additionally, one major U.S. auto lender failed to report its earnings, which may be a sign that smaller companies may also delay their earnings reports.