Monday, December 5, 2016

DOT Reports September Vehicle Miles, 2.9% Above Last Year, But...

The Department of Transportation reported 265.5 Billion individual vehicle miles driven in September, which is about 2.9% above last September.  This is consistent with motor gasoline sales.  However, gasoline sales have subsequently fallen below 2015 levels.  By straightforward logic, we should see October vehicle miles decline to at/below 2015 levels when the number is reported in a month.  

If the low gasoline sales reported in the last 10 EIA Weekly Petroleum Status Reports are reflecting something more secular, like a decline in economic activity or new driving megatrends, we should see the low numbers repeat through the end of year.  January will provide more confirmation, when holiday effects are behind us, unless unusual weather interferes.

In general, we drive much more in the summer, but also get better mileage (more rural interstate miles, less urban arterial/other).  Fuel economy has been improving at 0.5 MPG per year, roughly speaking, over the last three years: