An examination of recent trends in multimodal travel behavior among American motorists

ABSTRACT

According to national statistics, 87% of all trips in the United States are by automobile and 90% of commuters typically get to work by car. Statistics for individual trips or the main mode of commuting do not capture variability in individual travel behavior over time. This article uses the 2001 and 2009 National Household Travel Surveys to analyze recent trends in the share of multimodal motorists who use a car and also walk, bicycle, or ride public transport during a day or week. This article identifies trends of multimodal behavior among car users in the United States and provides profiles of these multimodal motorists.

During a typical day about 14% of American car users make at least two trips by foot, bicycle, or public transport, while during a typical week about 25% of motorists make at least seven trips by means of transport other than the car. Results from a bivariate analysis and logistic regressions suggest significant shifts toward more multimodal behavior among motorists between 2001 and 2009. Multimodal motorists tend to be younger, educated beyond high school, in households without cars, and live in high-density neighborhoods with access to a rail system. Results suggest that planning for walking, cycling, and public transport benefits a larger proportion of the U.S. population than suggested by traditional trip-based analysis.

KEYWORDS:

• Multimodal car user
• sustainable transport
• travel behavior
• trends 2001–2009
• USA

Funding

This research has been supported by the Mid-Atlantic University Transportation Center (MAUTC) of U.S. DOT's Research and Innovative Technology Administration (RITA), grant number DTRT12-G-UTC03.

Notes

¹ Our analysis included mode choice for access and egress trips to public transport. Excluding public transport access and egress trips from our analysis would decrease the share of individuals considered multimodal. However, because the share of all trips by public transport is relatively low in the United States, the difference in results is not large. We prefer to include public transport access and egress trips to more accurately capture modal variability at the person level. However, we recognize that travel demand forecasting typically excludes these trips. Excluding public transport access and egress would mean a change in the population share of the “day + 2” group from 11.0% to 10.2% in 2001 and 13.5% to 12.5% in 2009, and a change in the share of the “week + 7” group from 22.3% to 22.0% in 2001 and 25.1% to 25.0% in 2009.