by Michael Sivak, Sivak Applied Research

This analysis examined truck traffic as the percentage of all traffic on interstate highways in the individual states and the District of Columbia. The calculations combined the percentages of vehicle distances traveled by single-unit trucks and combination trucks (but not light trucks) published by the Federal Highway Administration. The data are for 2019. The 10 states with the highest and lowest percentages of truck traffic on rural and urban interstates are presented in the table below. (There are no rural interstates in the District of Columbia and Delaware.)

The percentages of truck traffic varied greatly among the states. For both rural and urban interstates, truck traffic was proportionally highest in Arkansas (36.1% rural, 30.5% urban) and lowest in Hawaii (4.6% rural, 1.9% urban). For the entire United States, truck traffic represented 23.7% of all traffic on rural interstates and 11.4% on urban interstates.

The 2019 data presented in this analysis somewhat underestimate the percentage of current truck traffic. This is the case because the pandemic has affected truck and passenger-vehicle traffic differently. Specifically, truck traffic in 2021 is generally higher than in 2019, while passenger-vehicle traffic is still down. For example, during the week of March 1 through March 7, 2021 (the latest available data), truck traffic on all interstates increased by 12% compared with the corresponding week in 2019, while passenger-vehicle traffic decreased by 9%.

Michael Sivak is the managing director of Sivak Applied Research and the former director of Sustainable Worldwide Transportation at the University of Michigan.