August 06, 2009 -
http://www.autoobserver.com/2009/08/cash-for-clunkers-generated-196-million-saar-in-july-week-edmundscom-calculates.htmlEdmunds.com calculates that the Seasonally Adjusted Annualized Rate (SAAR) of sales in the last week of July hit a whopping 19.6 million. The SAAR for the month was pulled up to 12.5 million -- it's highest level in a about a year, thanks to the end-of-month sales surge.
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In the months just before Cash for Clunkers launched, 39 percent of new car sales involved a trade-in. Since then, 51 percent do. Prior to the program, nearly 9 percent of trade-ins were vehicles that would have qualified as "clunkers." Since the launch, 39 percent of trade-ins qualify.
Most likely, people knew the program was coming and held off buying.