Ride-hailing accounts for an 83 percent increase in the miles cars travel for ride-hailing passengers in Denver's metro area, according to a study published this week in the journal Transportation by researchers at the University of Colorado Denver.

He collected exclusive driver data providing hundreds of rides throughout the Denver metropolitan area in fall 2016, according to the paper, "The impact of ride-hailing on vehicle miles traveled."

For this first-of-its-kind study, the researcher-driver collected real-time data and surveyed passengers for feedback and demographic information.

By surveying passengers, Henao learned that a combined 34 percent of his ride-hailing passengers would have taken transit, walked, or bicycled if ride-hailing hadn't existed.

"Vehicle miles traveled increased mainly due to two factors; additional empty miles from ride-hailing drivers going around without passengers, and ride-hailing substituting more efficient and sustainable modes such as transit, biking and walking," said Henao.

There is decrease in overall transportation efficiency due to more car miles on the road, often traveling without passengers.

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