Rising Fuel Efficiency Over Time

See Cheaper Oil Isn’t the U.S. Boon It Used to Be by Paul Kiernan and Christopher M. Matthews of The WSJ. Excerpt: 

"Fuel-efficient vehicles and a long transition away from heavy industry mean the U.S. economy now consumes just 0.4 barrels of oil to produce $1,000 of gross domestic product, down from 1.1 barrels in 1972, said Martin Stuermer, a senior research economist at the Dallas Fed."