SAN FRANCISCO, CA - MAY 09: Bicyclists ride along Market Street on May 9, 2013 in San Francisco, California. The San Francisco Municipal Transportation Agency has installed an automated real-time bike counter, also known as a bicycle barometer, on Market Street that will display daily and annual counts. According to the SFMTA, the number of cyclists on the streets of San Francisco has surged 71 percent between 2006 and 2011. (Photo by Justin Sullivan/Getty Images)
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Getty Images News Justin Sullivan