Vehicle Miles Driven: Population-Adjusted Fractionally Off the Post-Crisis Low, Doug Short, Advisor Perspectives, June 24, 2013

Doug Short is a financial advisor with a Canadian financial firm who has maintained a blog that tracks economic and financial developments and offers advice (mostly from other advisors) on the state of the stock and bond markets since well before joining the Canadian firm.  Periodically, he veers off course a little, such as this article on vehicle miles traveled (VMT), a topic that very much pertains to the urbanization of Reston around the Silver Line.

The article is long and a bit technical, but very readable.  Short is especially adept a presenting clear charts to illustrate the points he is trying to make.  In this post, he points out the post-2007 trend in the US for auto use to have declined on a per capita basis--and gasoline prices didn't have much to do with it.  Yes, total miles are up, but so is the driving population.  The reduction in VMT per capita has a number of drivers.  Here are the ones he points to:

As is readily apparent, the (VMT) correlation (with gasoline prices) is fairly weak over the entire timeframe (+0.30). (Comment:  The weak, but positive correlation indicates VMT/capita went up over time despite gas price increases.) And, despite the volatility in gasoline prices since the onset of the Great Recession, the correlation since December 2007 has been even weaker (-0.26). There are profound behavioral issues apart from gasoline prices that are influencing miles driven. These would include the demographics of an aging population in which older people drive less, continuing high unemployment, and the ever-growing ability to work remote in the era of the Internet.

I would submit--as those who are experts in the would suggest--that at least a couple of other behavioral issues have been major drivers:

• Generally, the continuing greater urbanization of America with people living closer to where they work, shop, and play.  
• More specifically, the strong millennials' preference for living near where they work (so they can walk or bike) and/or good (safe, reliable, speedy) public transit.

Click here to read Short's post on declining VMT/capita.