Truck mpg has lagged for decades: Will diesel and electric pickups do better?

2016 Chevrolet Colorado Duramax dieselNearly all vehicle types now achieve more than double the gas mileage that they achieved in 1975, when the EPA started compiling trends for vehicle emissions and fuel economy. All except pickups, that is. While the U.S. fleet of new vehicles has been becoming more fuel-efficient at a rapid rate in recent years, the rate of truck mpg...