I’ve excerpted an article below, showing that, while the US Economy nominally grew from a GDP of $13.8 Trillion to $17.4 Trillion, the US Trucking Industry diesel consumption fell from 4.3 million barrels per day to 3.8 million barrels from 2007 to 2014, and it had nothing to do with gas mileage.
For GDP to have grown 26%, while trucking fell over 10%, seems to be a big disconnect to me. All else being equal (never) it would appear that GDP growth was all due to 4.5% inflation above what the government number crunchers are telling us.
As a secondary note, I see in the chart below that Trucking Fuel Efficiency fell off a cliff between 1965 and 1970 – from 7.8 to 5.5 miles per gallon. Does anybody out there know why?