I wonder what effect the "cash for clunkers" program had on cars below the rebate incentive for that. It had to have a substantial effect on market for older cars.
The effect was probably moderated by the 18 mpg cutoff for fuel efficiency. My midsize 1997 sedan does about 24 mpg, so it wasn't eligible, and at this point it is way down at the bottom of the used car market, not something that most buyers would spend much time looking at.