Here is an interesting plot from Paul Hodges (posted March 20, 2015) that shows U.S. vehicle miles traveled per adult vs. the price of gas, through 2014. The VMT per year, although showing a slight increase during the past year, has decreased 8.4 percent from 13,274 in 2004 to 12,162 in 2014.

The full report may be seen by clicking on this link.