In the last decade, the population in the county has grown, with more homes and more potential drivers, but the growth has not put more vehicles in local driveways and garages.
The number of eligible drivers in Johnson County — residents who are at least 16 years old — rose by 10 percent from 2010 to 2016, but the number of vehicles registered to local residents dropped by 1 percent during that same time, a trend happening in counties across central Indiana, according to data from the Indiana Bureau of Motor Vehicles.
Older residents giving up driving, teenagers deciding to put off getting a car and the increasing costs of purchasing and maintaining a vehicle could all play a role in why the number of vehicles local residents own has dropped, said Jerry Conover, the director of the Indiana Business Research Center at Indiana University.
The popularity of transportation services, such as Uber and Lyft, has also grown, giving people an alternative to get places without a vehicle of their own, he said. More local residents are also using public transportation, with the number of trips each year on Access Johnson County buses continuing to grow, reaching 85,000 in 2016.
But at the same time, local and state traffic studies continue to show more vehicles driving on local roads, leading local officials to widen and redesign roads across the county.
The county’s population has continued to grow, with more than 107,000 residents age 16 and over in 2010, and more than 118,000 in 2016, according to Census data.
But families have multiple reasons why they may have decided to own fewer cars, Conover said.
The cost of owning a car, along with insurance, gas and rising taxes, such as registration fees, can also play a role in whether teens are able to get vehicles of their own, Conover said. For example, 10 years ago Johnson County joined several other Indiana counties in creating a wheel tax, which ranges from $15 to $40 per year, depending on the type of vehicle. Lawmakers approved a $15 increase to vehicle registration fees that will go into effect next year.
In addition, a gallon of gas costs an average of about $2.30, according to gasbuddy.com. In the past decade, that price has ranged from about $1.50 to $4 a gallon, and this year, lawmakers increased the state gas tax by 10 cents a gallon.
Studies have also been showing that teens are waiting longer before getting their license, which could also mean a family needs fewer vehicles.
Nationally, the percent of teenage drivers has been dropping, according to data from the Federal Highway Administration.
In 2015, about 50 percent of teens had driver’s licenses, compared to 52 percent in 2010 and 56 percent in 2007, the data showed. Indiana had 220,000 teenage drivers in 2008, compared to 187,000 in 2014, according to Federal Highway Administration data.
Another key factor in looking at driving trends is whether the population is aging, Conover said.
As the Baby Boomer generation nears retirement, some may decide they don’t need as many cars for their household, he said. In Johnson County, the percentage of residents nearing retirement — or age 65 and older — has risen recently, going from 12.3 percent in 2010 to 14.3 percent in 2016, Census data showed.
Across central Indiana, some other counties have not had a drop in the number of registered vehicles, such as in Hamilton, Boone and Hendricks counties, but the increase has not kept up with the population growth, according to the state bureau of motor vehicles data.