In the 1990s and early 2000s, fuel economy decreased while vehicle weight increased. In recent years, however, light-duty vehicle manufacturers have employed advanced technologies to improve both performance and fuel economy.
As a result, average fuel economy for all light-duty vehicles produced has improved nearly every year since 2004, and in 2018 rose to a record high of 25.4 miles per gallon, according to the US Department of Energy (DOE).
Despite a 128% increase in horsepower and 49% improvement in acceleration from model year 1980 to 2018, the overall fuel economy of light-duty vehicles improved 32% during that period. The data are based on production-weighted averages.