A brief study by Dr. Michael Sivak, Director, Sustainable Worldwide Transportation at the University of Michigan Transportation Research Institute (UMTRI) concludes that despite the absolute number of vehicles in the US having reached a maximum in 2008, it is highly likely that—from a long-term perspective—the absolute number of vehicles in the US has not yet peaked.
However, he notes, the rates of vehicles per person, licensed driver, and household reached their maxima prior to the onset of the current economic downturn. As a result, Sivak concludes, it is likely that the declines in these rates prior to 2008 reflect other societal changes that influence the need for vehicles (such as, increases in telecommuting and in the use of public transportation). Therefore, the recent maxima in these rates have better chances of being long-term peaks as well, he suggests.
The US currently has about 253 million registered motor vehicles of all types, according to the Federal Highway Administration (FHWA). The focus of this research was on light-duty vehicles (cars, pickup trucks, SUVs, and vans). The number of light-duty vehicles in 1984 stood at 156.8 million. The number reached a maximum of 236.4 million in 2008. In 2011 (the latest year available), the number was 233.8 million.
The number of vehicles reached a maximum—at least for the time being—in 2008, the year of the onset of the current economic downturn. The value in 2011 was somewhat higher than the lowest post-2008 value, which was reached in 2010. This is the expected pattern, with the changes in the number of vehicles lagging the changes in the general economy.
Given that US economic conditions are improving and that the US. population is expected to continue to grow, it is highly likely that the maximum number of vehicles reached in 2008 will be surpassed in the near future.—Michael Sivak
In terms of the rates of vehicles per three variables of interest:
Vehicles per person. In 1984 there were 0.66 vehicles per person. This rate increased to a maximum of 0.79 in 2006. The latest rate—for 2011—was 0.75.
Vehicles per licensed driver. In 1984 there were 1.01 vehicles per licensed driver. This rate increased to a maximum of 1.16, which was reached in 2001, 2005, and 2006. The rate in 2011 was 1.10.
Vehicles per household. In 1984 there were 1.84 vehicles per household. This rate increased to a maximum of 2.05, which was reached in 2001, 2005, and 2006. The rate in 2011 was 1.95.
...because the changes in the rates from 2008 on likely reflect both the relevant societal changes and the current economic downturn, whether the recent maxima in the rates will represent long-term peaks as well will be influenced by the extent to which the relevant societal changes turn out to be permanent.—Michael Sivak