Survey: When you have an average of 71 people per car, people choose to ride in cars less

After One Year, Zipcar Drives Transportation Change in Baltimore - Jul 18, 2011

The data reveals that during the past year, Zipcar members in Baltimore, whom the company calls "Zipsters," own fewer cars, drive less and use public transportation more often than they did prior to joining.
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The number of Zipsters taking five or more car trips in a month has decreased from 38 percent, to 12 percent
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Zipcar is the world's leading car sharing network with more than 575,000 members and over 8,000 vehicles in urban areas and college campuses throughout the United States, Canada and the United Kingdom.