PHOENIX -- New data released by the Department of Transportation suggested people are driving less these days.

The trend of declining driving continued into its second year, with 3.7 billion fewer vehicle-miles traveled in December 2008 compared to December 2007, official statistics showed.

"The nation's driving decline is another indication of just how important the president's economic recovery plan is," said Ray LaHood, U.S. Transportation Secretary.

Statistics showed the western states experienced the biggest decline in vehicle-miles traveled at 4.8 percent. Oregon and Washington led with the largest dip, due, in part, to an unusually large amount of snowfall, DOT said.

Despite an overall decline, 17 states posted a slight increase in driving miles. Colorado led the states with 5.4 percent more driving miles in December 2008 than in December 2007, DOT said.