We May Have Already Hit Peak Car

Since a high water mark of 2008, the number of cars on the road has dropped. Is it just a bad economy, or is society shifting away from our automobile-dependent roots?

We May Have Already Hit Peak Car
Traffic, Nic Sedlock via Flickr

You wouldn’t know it from the cars that clog streets across the country every day during rush hour, but the number of registered vehicles on the road has begun to stagnate. Michael Sivak, a research professor at the University of Michigan Transportation Research Institute thinks this may be a sign of a larger phenomenon: peak motorization in the U.S.


In a new paper, Sivak analyzes the overall number of light duty vehicles (i.e. cars and pickup trucks) on the road, as well as rates per person, per household, and per driver, from 1984 to 2011. Here’s the analysis of registered light duty vehicles:

As you can see, the number of registered vehicles peaked and then dropped after 2008, most likely as a result of the economic downturn. In 2008, there were 236.4 million light duty vehicles on the road– 2.6 million more vehicles than in 2011. Here’s the more detailed graph:

Current trends indicate that vehicle registration will surpass 2008 numbers, if only because the economy is bouncing back and the country’s population is expected to balloon. But that doesn’t tell the whole story. Sivak explains in his paper:

Each of the three rates (the number of vehicles per person, per licensed driver, and per household) reached a maximum (to date) between 2001 and 2006–prior to the start of the current economic downturn in 2008. In other words, these rates started to decline not because of economic changes but because of other societal changes that influence the need for vehicles. (The changes in the rates from 2008 on reflect both the postulated societal changes and the economic downturn.) Thus, in contrast to the absolute numbers, the recent maxima in the rates have a better chance of being long-term peaks as well.

Those societal changes include things that we talk about frequently here: an increase in the numbers of both telecommuters and people who take public transportation to work. Sivak doesn’t mention it, but it’s safe to say that the decline of the suburbs and growth of cities also will play a role in decreased car ownership in the future. The rise of sharing economy startups that let people easily hitch rides or rent vehicles for quick trips (like Lyft, Sidecar, Getaround, and Zipcar) will also contribute to the decline.

Assuming that all of these trends continue on their current path–and they probably will–then automakers should be worried. There’s a reason that even traditional automakers are getting into the carsharing business.

About the author

Ariel Schwartz is a Senior Editor at Co.Exist. She has contributed to SF Weekly, Popular Science, Inhabitat, Greenbiz, NBC Bay Area, GOOD Magazine and more.