Here's the best explanation I've found....

Is 'Cash for Clunkers' for Chumps?

"...Edmunds says the average sale price of a brand new car is $27,800, whereas the average price of a used car is $13,900. That's a savings of roughly $14,000 achieved simply by letting somebody else be the chump who buys the brand new vehicle!

Still want to be green? There are plenty of 3-year-old vehicles with excellent fuel economy. The technology hasn't changed much in the past few years. It's also a great time to buy used because cars and trucks are incredibly reliable these days. They can easily chug along for 200,000 miles with few problems.

So, you decide. Would you rather save $4,000? Or $14,000?
Cash for CHUMPS...