DOES TELECOMMUTING REDUCE VEHICLE-MILES TRAVELED? AN AGGREGATE TIME SERIES ANALYSIS FOR THE U.S.

This study uses a multivariate time series analysis to estimate the impact of telecommuting on vehicle-miles traveled (VMT) of personal transportation. Aggregate nationwide data spanning 1966-1999 for all variables except telecommuting, and 1988-1998 for telecommuting was used in the analysis. The analysis was conducted in two stages. In the first stage, VMT (1966-1999) was modeled as a function of conventional variables representing economic activity, transportation price, transportation supply and sociodemographics. In the second stage, the residuals of the first stage (1988-1999) were modeled as a function of the number of telecommuters. The authors also assessed the change in annual VMT per telecommuter as well as VMT per telecommuting occasion for 1998. The models suggest that telecommuting reduces annual VMT on the order of 0.8% or less. Even with such small impacts, telecommuting appears to be far more cost-effective in terms of public sector expenditures when informally compared to similar reductions in VMT due to public transit ridership. Other policy implications are discussed