- Statistical analysis of the 74 largest urbanized areas in the U.S. over a 26-year period suggests that increasing transit utilization does not lead to a reduction in traffic congestion; nor does decreasing transit utilization lead to an increase in traffic congestion.
- Policies designed to promote transit utilization can in certain instances increase traffic congestion-as appears to have been the case in Portland, Oregon.
- Vehicle-miles traveled per freeway lane-mile is strongly correlated with traffic congestion: the more people drive relative to available freeway capacity, the worse congestion gets.
- Data from New York and Los Angeles indicate that the most effective way to increase transit utilization is by reducing fares, as well as by improving basic, pre-existing service.
