Updated: The

Federal Highway Administration

reported yesterday that travel during August 2008 on all roads and streets in the U.S. fell by -5.6% compared to August last year. According to Secretary of Transportation Mary Peters, this was the largest ever year-to-year decline recorded in a single month.

YTD through August 2008 fell by -3.3% compared to 2007.



The ten consecutive monthly declines (November 2007 through August 2008) in miles driven compared to the same month in the previous year is almost a record, and represents one of the most significant adjustments to driving behavior in recent history.



On a moving 12-month total basis, traffic volume in August fell to 4.5-year low of 2.929 trillion miles, the lowest level since March of 2004 (see chart above), and this measure has fallen in ten of the last 12 months.



Bottom Line: The moving 12-month total traffic volume in August 2008 (2.929 trillion) is below the August 2007 level (3.008 trillion) by 78.911 billion annual miles driven. At an average fuel efficiency of 20 m.p.g., and an average gas price of $3 per gallon over the last year, that reduction in miles driven represents almost a $12 billion annual savings for American consumers. That's in addition to the much larger $200 billion annual savings for consumers from the drop in gas prices from $4.12 per gallon to $2.71 since August ( August marks the tenth consecutive month of traffic volume decline compared to the same month in the previous year. Travelthrough August 2008 fell by -3.3% compared to 2007.The ten consecutive monthly declines (November 2007 through August 2008) in miles driven compared to the same month in the previous year is almost a record, and represents one of the most significant adjustments to driving behavior in recent history.On a moving 12-month total basis, traffic volume in August fell to 4.5-year low of 2.929 trillion miles, the lowest level since March of 2004 (see chart above), and this measure has fallen in ten of the last 12 months.The moving 12-month total traffic volume in August 2008 (2.929 trillion) is below the August 2007 level (3.008 trillion) by 78.911 billion annual miles driven. At an average fuel efficiency of 20 m.p.g., and an average gas price of $3 per gallon over the last year, that reduction in miles driven represents almost a $12 billionsavings for American consumers. That's in addition to the much larger $200 billion annual savings for consumers from the drop in gas prices from $4.12 per gallon to $2.71 since August ( gas data ), since consumers save about $1.42 billion annually for every penny decrease in gas prices.

It will be interesting to see how the significant fall in gas prices in September and October 2008 affects driving behavior, and we'll know in about a month from the next FHA report on September 2008 traffic volume.