The value of travel time savings in evaluation

Values of travel time enter the appraisal scheme both as values for modelli ng and forecasting and as values for use within project evaluation. This pa per considers whether and how travel time values should be used within eval uation. The basic theories of private and social travel time valuation are set out. Issues such as the valuation of working time savings, the case for segmenting values by journey purpose and length, sign and size of time sav ings and mode of travel, and the income elasticity of the value of time, ar e reviewed. Two of the main conclusions are that time is a scarce resource and should be valued but that direct use of willingness to pay values is in appropriate for social appraisal of projects. Some form of social weighting scheme is required. (C) 2001 Elsevier Science Ltd. All rights reserved.