Here’s a chart from an wonky, slightly-old, provocative book called Transportation for Liveable Cities by a Pennsylvania transportation professor named Vukan Vuchic. It shows Vuchic’s estimates of the total costs for different travel choices in a dense urban city, showing a peak-hour car trip with tolls and parking, an off-peak car trip without those costs, a typical urban transit trip, and a longer regional commuting transit trip.
Here’s the chart:
In the book, Vuchic describes the chart and makes the following sequential conclusions:
The chart chows the total costs for the same four cases. The subsidies for transit include operating subsidies and a certain value for infrastructure investment. The latter amount may vary from none for bus transit on streets, which has virtually no infrastructure, to extensive for rapid transit or busways [….] The four diagrams […] lead to the following important observations.
- Travel costs by both car and transit vary considerable with location and time of travel. Total car travel costs are particularly high in large cities during peak hours because of parking, social, and environmental costs.
- The direct, out-of-pocket cost of car travel consists mainly of the cost of fuel, which is extremely low, and parking fees and tolls, when these are charged. When parking is subsidized (“free”), which is the case virtually everywhere except in city centers, the direct cost of auto travel is virtually negligible.
- Because most people decide how far to travel and which mode to choose on the basis of direct costs only, this cost structure greatly stimulates driving. This follows the fact that underpriced services are overused. The ultimate distortion of pricing in urban travel occurs when people who drive company cars treat their travel as entirely free.
- With respect to costs, the low direct cost of driving renders fully priced transit noncompetitive with the car. Thus, underpricing car driving through direct subsidies, and its consequent unrealistic car structure, results in the need to subsidize transit.
- The direct costs represent, in most cases, the “tip of the iceberg” of the total costs of car travel. Based on the AAA’s 1995 estimates, on average, direct costs of driving amount to only 13 percent, fixed costs 87 percent, of user costs. Fixed costs consist of depreciation, insurance, repairs, and other costs not directly dependent on individual trips.
- Social costs of driving (mostly congestion imposed on other street and highway users, including car and truck drivers, transit riders, and pedestrians) and environmental costs (affecting society at large) are not paid by car users at all.
- Environmental costs and the impacts of highway travel are not paid by users either. They represent another major cost element of the “under-the-surface portion of the iceberg.” The total indirect costs, including the user’s fixed costs, subsidies, and unpaid costs absorbed by society and the environment, amount, in the case shown, to more than 92 percent of the total costs.
The whole book goes on like that, and is full of similar charts and analysis. Especially with the price of gas reaching 90s-era levels, I’m not sure that much of Vuchic’s conclusions have changed.