The person who calculated this bit of information went to high school in Pittsburgh, PA. He is now (and has been) a professor at The University of West Virginia in Morgantown, West Virginia for the last forty some years.
I never looked at the CASH FOR CLUNKERS program in such depth.
Think of it this way:
A clunker that travels 12,000 miles a year at 15 mpg uses 800 gallons of gas a year. A new vehicle that travels 12,000 miles a year at 25 mpg uses 480 gallons a year. 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 is about 5 hours worth of US consumption. More importantly, 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 we saved.
I'm pretty sure they will do a great job with our health care though.