Project at a Glance

Title: Impacts of compressed workweek on total vehicular trips and miles traveled.

Principal Investigator / Author(s): Giuliano, Genevieve

Contractor: University of Southern California

Contract Number: A132-136

Research Program Area: Economic Analysis

Topic Areas: Behavioral Change, Impacts, Mobile Sources & Fuels


The purpose of this project was to evaluate the effectiveness of compressed work-week schedules (CWW) as transportation control measures. Compressed work week schedules allow a full-time regular shift (forty hours per week) to be worked over fewer than five days, thus reducing the number of work trips per week compared to a regular five day schedule. The most common types of CWW are the "4/40" schedule (four days of work per week, ten hours of work per day), and the "9/80" schedule (nine days of work per two week period, 8.5 to 9 hours of work per day). Both types of CWW schedules are included in the analysis. The potential of CWW to reduce travel and improve air quality depends on how daily travel patterns are affected when more hours each day and fewer days each week are worked. Since most employees on CWW schedules have Friday or Monday as the extra day off, less weekday work travel may be at least partially offset by more weekend non-work travel. Trips also may be combined in different ways or distributed differently through the day.

We conducted our analysis by comparing travel patterns of workers on CWW schedules with those of workers on regular schedules. Our data were obtained by conducting employee surveys at eleven work locations within Los Angeles and Orange Counties. Survey participants were asked to complete a seven-day travel diary, describing each trip taken over the seven-day period. Several different aspects of travel were examined, such as total weekly travel, travel by private vehicle, number of trips, etc. We accounted for individual socioeconomic and demographic factors that are known to both to affect travel and affect the likelihood of working a CWW schedule in our analysis in order to quantify the effects of the work schedule as accurately as possible. Our analysis revealed that there is a great deal of variability in weekly travel patterns, making it difficult to make precise estimates of the impact of CWW on travel patterns. Individual characteristics (gender, age, etc.) have a more powerful effect on travel than the work schedule. We found that CWW is associated with significantly less work travel and no measurable increase in non-work travel.

For questions regarding this research project, including available data and progress status, contact: Research Division staff at (916) 445-0753

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