Has motorization in the U.S. peaked? Part 7: update through 2013

Abstract

In Part 5 in this series of reports, I examined the changes from 1984 to 2012 in the number of registered light-duty vehicles, and the corresponding changes in distance driven and fuel consumed. The units of the analyses were both the absolute numbers and the rates per person, per driver, per household, and (where appropriate) per vehicle. The main finding of that report was that the respective rates all reached their maxima around 2004. I argued that, because the onsets of the reductions in these rates preceded the onset of the recession in 2008 by several years, the reductions in these rates likely reflect fundamental, noneconomic changes in society. Therefore, these maxima have a reasonable chance of being long-term peaks as well. The present report provides a brief update on these measures through 2013. The main findings are as follows: (1) Despite the population growth, the absolute amount of fuel consumed by light-duty vehicles decreased by 11% during the period 2004 (the year of maximum consumption) through 2013. (2) The reductions in the rates per person, per driver, per household, and (where appropriate) per vehicle from the corresponding maxima (around 2004) to 2013 were greatest for fuel consumed (averaging about 17%), followed by distance driven (about 8%) and number of vehicles (about 5%). (The fact that the reductions were greatest for fuel consumed reflects, in part, the added contribution of the improvements in vehicle fuel economy.) (3) The 2013 rates of vehicles and distance driven were comparable to the rates in the 1990s. The 2013 rates of fuel consumption were lower than the rates in 1984—the first year of this analysis. (4) There is no evidence in the 2013 data that the recent reductions in the rates were temporary. Indeed, out of the seven rates examined for number of vehicles and distance driven, four showed a decrease from 2012 to 2013 and three showed an increase. However, the changes in these rates were all within ±0.7%, suggesting that the situation in 2013 was generally the same as in 2012. (All four rates for fuel consumed decreased from 2012 to 2013, with the largest decrease of 1.1%.)