Nearly half of Americans ages 6 and older, or 137.9 million individuals, participated in at least one outdoor activity in 2010, making 10.1 billion outdoor outings, according to the 2011 Outdoor Recreation Participation Topline Report.

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Biking in the United States is treated primarily as a leisure activity, with 73 percent of cyclists telling the National Bicycle Dealers Association (NBDA) they ride for recreation.

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