A growing number of Americans living in cities are joining the ranks of those who have decided they don't need to own a car.
According to a new study by University of Michigan Transportation Research Institute professor Michael Sivak, as of 2012, 9.22 percent of American households did not own a vehicle—a slight decrease compared to the prior year.
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That decrease snapped a four-year run where the percentage of American homes without a vehicle had increased.
Meanwhile, in 21 of 30 U.S. cities studied by Sivak, the percentage of homes that do not own a car, truck or SUV showed an increase in 2012 compared to 2007, the year with the lowest recent proportion.
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New York has the highest percentage of households without a vehicle, 56.5 percent, and is one of six cities where at least 30 percent of homes do not own a vehicle. The other five are Washington, Boston, Philadelphia, San Francisco and Baltimore.
The study's results are the latest indication that a number of people in the U.S. do not own a vehicle due to the economy's slow recovery, the rising cost of buying a vehicle and a growing number of other transportation options, including car share programs and mass transit.
—By CNBC's Phil LeBeau. Follow him on Twitter @LeBeauCarNews.
Questions? Comments? BehindTheWheel@cnbc.com.