Wednesday, March 11, 2009

The momentum of a juggernaut


If you want to get an appreciation for just what a juggernaut the US driving public is, check out the following graph. I got it from Green Car Congress.

This graph goes back to 1983 and shows a steady, almost inexorable, rise from 1.6 trillion vehicle miles driven annually to peak at just over 3 trillion vehicle miles. There are slight periods where the graph goes horizontal for a few months (which seem to map to various recessions). However, the biggest actual drop EVER has happened at the start of 2008, when oil prices were pushing gasoline prices through the roof. This should allow economists to get some idea of the elasticity of gasoline. I'd assume it isn't much.

What I find striking is how much it is rising. I'd like to compare this to population. I'd also like to have a current version of this graph - one that includes the financial and job-market meltdown of late 2008. Gas prices have fallen, but when people aren't working, they aren't commuting. The reason I find this so arresting is that it took $4+/gallon prices to push drivership down to 2006 levels! I moved to Los Angeles in 2002 - what is the likelihood that this graph will drop to those levels?