The squeeze

As has been well documented, the consumer credit market has become much tighter over the past few years. "Back in 2007, anyone could get a new-car loan," explained Steven Lang, a used-car dealer in the Atlanta area. "Today there are a lot of people out there who are broke. As close as many of them can get to a new car is a 5-year-old PT Cruiser."

If you bought a new car during the past three or four years and haven't fallen victim to a calamitous job loss or worse, you probably still have sterling credit and could qualify for another new-car loan. You're a precious, creditworthy commodity to a new-car dealer. But you're of no value to that dealer at all if he doesn't get you into the market. And he's got plenty of buyers without such blinding shiny credit scores ready to buy a used car. And the subprime credit market has rebounded somewhat.

"It's far easier to get someone into a used car than a new one," Lang said. "And there's more money out there for used cars than new ones."

The used-car market is huge and diverse, running from ancient beaters sold for a few hundred bucks on Craigslist to classics that go for millions at Sotheby's. It's easy to overgeneralize about the heart of the market, but most used cars are sold as transportation to people of moderate incomes who must finance their purchases. Those people don't just want cars, they need cars, or they're unable to fully participate in the U.S. economy. And they're feeling squeezed more than ever.

That, more than anything else, is why your dealer wants your car.

Change is coming

Like every market, the market for used and new vehicles is dynamic. How the car business values your used vehicle right now isn't how it's going to value it next week, next month or next year.

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For the immediate future, it looks as if used-car values will stay high, as new-car manufacturers have adjusted production to reflect market demand. "Prices have likely peaked," said NADA's Banks. "But it's a strong market with strong fundamentals."

Ford, General Motors and Chrysler aren't pumping out cars to keep their factories busy and then dumping them into rental fleets or pushing them with supercheap leases, as they were able to in years past. As a result, there aren't likely to be as many new cars becoming used ones over the next few years. And used cars remain a good value relative to new cars.