(e) Demand Elasticity with Respect to Travel Time Good with (1992) estimated that the elasticity of vehicle travel demand at urban roads with respect to travel time is -0.27 and -0.57 in the short and long run, respectively (the values for rural roads were -0.67 and -1.33, respectively ). The elasticities of demand with respect to auto travel times, by trip type and mode, are summarized in Table 3.5. These are long-term elasticities in areas of high vehicle ownership: over 0.45 vehicle person (TRACE, 1990). Also, demand elasticities with respect to travel time were presented by SACTRA (1994) and separately for auto and bus in vehicle time, and for transit-related walking and waiting time. By Booz Allen Hamilton (2003).