Transit Benefit Index: A Comprehensive Index for Capturing Externalities in Transit Planning

Document Type

Journal Article

Publication Date


Subject Area

place - south america, place - urban, mode - bus, mode - bus rapid transit, mode - car, planning - methods, planning - travel demand management, economics - subsidy, economics - capital costs


planning and analysis, public transportation, planning and development, general


This research provides a methodology for estimating the total societal benefit generated from substituting private vehicle trips with public transportation trips. The external costs of private and public transportation were estimated using a base case travel demand model and then a mode shift was simulated to calculate the effects of shifting one full transit unit (e.g., bus) of demand from a private to public mode. This shift was performed for all origin–destination (O-D) pairs in a region to find the O-D pairs that resulted in the greatest net benefit. These benefits were then normalized using the total automobile vehicle kilometers traveled removed from the network to generate a “transit benefit index.” This methodology was applied to a case study of the city of Bogotá, Colombia. A total of 102 scenarios were simulated: a 2 in base case, and 10 total sensitivity analyses, each including two transit provision alternatives. The results were contrasted with the cost of a new transit unit—a new bus in this case—revealing that the total economic benefit derived from 1 year of increased transit ridership was larger than the financial cost of a new bus to the transit operator. These results suggest that the City of Bogotá should consider further subsidies to transit fares to increase ridership and mitigate externalities.


Permission to publish the abstract has been given by SAGE, copyright remains with them.