Challenge

Understanding how, when, and why residents of the U.S. move from place to place throughout a typical day is key for the FHWA, state departments of transportation, regional metropolitan planning organizations (MPO), and other policymakers in fields like safety and the environment.

Maintaining national transportation data trends in travel behavior across time is a long-standing goal of the National Household Travel Survey (NHTS), which has been conducted every 5 to 8 years since 1969 and was conducted most recently in 2016 and 2017.

Helping to identify transportation system needs and plan for improvements are other functions of the NHTS.

Solution

For the first time in the history of the NHTS, the 2017 survey was based on an address-based sample of respondents rather than the traditional random digit dialing approach.

The foundation of the 2017 NHTS’s success was the creation of a sampling design that addressed the needs of the FHWA and the 13 add-on state and regional programs that participated in the NHTS.
The next component included designing a questionnaire that collected key household demographic and vehicle information, trip destinations and durations, distance traveled, and purpose of trips during an assigned 24-hour period of time.

The 2017 NHTS featured a multimode methodology designed to elicit higher response rates than typical regional household travel surveys. Westat recruited respondents through a mail-back paper questionnaire designed to increase survey participation. Westat mailed travel logs to all recruited households with instructions on how to record their travel. Respondents were encouraged to use a personal identifying number to report their trip information on the survey’s website after their assigned travel date was completed. Geocoded address information was collected for all trip destinations.

Westat conducted the survey over 13 months to allow for annual estimates of travel behavior, including seasonal differences not traditionally captured in state and regional household travel surveys.

Results

This was the third time that Westat conducted the NHTS. Westat successfully collected data from more than 129,000 households across the country. This included more than 26,000 households for the national sample and nearly 103,600 for the 13 states and regional planning organizations that chose to integrate their data collection needs with the NHTS. Westat prepared the survey data for analyses. The FHWA made the dataset available to participating states and regions and to the public. Westat also prepared and delivered specific trip detail files for each of the 13 add-on programs; these datasets provide confidential information that is not made available to the FHWA or the general public.