Estimation of Social Costs of Transport in Japan

Abstract

Using a dataset of 111 Japanese cities in 2005, the article estimates the social costs of car transport and analyses the structure of the components of and the relationship between social costs and city size. The following major results are obtained. First, the social costs of vehicular transport increase at an accelerated pace as city size becomes larger. Secondly, while the construction of roads does not work to decrease the social costs of vehicular transport, public transport has a tendency to decrease such costs, although with minimal effect. Thirdly, the traffic congestion component represents more than 45 per cent of the total social cost of vehicular transport. Cost due to global warming accounts for 5–11 per cent of the total. Fourthly, the social costs of vehicular transport are about 8 per cent of GDP. Fuel tax for cars covers only 16.3 per cent of the social costs of regular car use.