Marginal societal costs of traffic (composite+car) as a function of composite fraction. A: Societal costs (excluding subsidies for composite traffic) during different periods of day. B: Subsidies to composite ticket prices needed to reach the composite fraction target (i.e., to make that fraction of current private car passengers to favour composite traffic according to the model) during different periods of the day. For comparison, the current subsidies to public transportation in the Helsinki metropolitan area are on the range of 380 000 € per day . C: Societal costs (including subsidies) during daytime with extending areal coverage of composite traffic (starting from the most densely populated areas). The legend shows the number of inhabitants living in the covered area. The pink curve (538100 inhabitants) is the city of Helsinki).
Tuomisto and Tainio BMC Public Health 2005 5:123 doi:10.1186/1471-2458-5-123