the per-dollar benefit/cost of "Cash for Clunkers"

I don't know about the precision of the numbers, but they sound reasonable. Anyway, it underlines what we know, intuitively, to be an inefficient program-- even if it had been run well (hat tip: Greg Clark)...

So, the average Cash for Clunkers transaction will reduce US gasoline consumption by 320 gallons per year.

They claim 700,000 vehicles so that's 224 million gallons saved per year.

That equates to a bit over 5 million barrels of oil.

5 million barrels of oil at $70 per barrel costs about $350 million dollars.

So, the government paid $3 billion of our tax dollars to save $350 million.

We spent $8.57 for every dollar saved.

How good a deal was that???

And then, a punchline I had used earlier:

They'll probably do a great job with health care though!