The share of underwater trade-ins toward new-vehicle purchases has been rising for four years, but in the third quarter the average amount owed reached a record high.

According to Edmunds, 29% of trade-ins carried negative equity in the quarter, down one percentage point from the start of the year but up the same amount from a year earlier. And buyers who traded in vehicles owed an average of $7,107 more than their cars were worth, up $202.

Buyers who rolled negative equity into a new car loan financed an average of $57,235 with an average monthly payment of $952. And with an average annual percentage rate of 8%, negative-equity buyers are estimated to pay $16,610 in interest over the life of their loans.

While many consumers are choosing longer loan terms to try and offset the cost, Edmunds said that only increases their risk of remaining underwater for longer.

The car shopping and review site noted the widening gap between new-vehicle buyers who have negative equity and the general market. When compared with the average new-vehicle buyer, those who rolled over negative equity “financed roughly $12,600 more, paid an additional $165 per month, and were on track to incur nearly $6,700 more in lifetime interest.”