The Impact of Increased Fuel Economy for Light-Duty Vehicles on the Distribution of Income in the United States
David Greene and Jilleah Welch, for Oak Ridge National Laboratory and Energy Foundation, September 2016
This report describes the results of statistical estimation of models of scrappage rates and survival probabilities as a function of vehicle age for U.S. light-duty vehicles. The data used are counts of vehicles in operation by vehicle type and model year for calendar years 2002-2020, which allows scrappage functions to be estimated for years 2003-2020. Models were estimated for three vehicle types: passenger cars, SUVs and vans, and pickup trucks. The models are structured to estimate trends in scrappage and survival rates over time for each vehicle type. Modified logistic functions were found to fit the data well, with R2 values of 0.99 and statistically significant trends and fixed effects for each vehicle type. Results of estimation via nonlinear least squares indicate that life expectancies for all three vehicle types increased over the study period by 2-3 years for passenger cars, 3-4 years for SUVs and Vans, and 5-6 years for pickup trucks. By 2020, median expected lifetimes ranged from about 17 years for passenger cars, and 20 years for SUVs and vans, to about 25 years for pickup trucks.