be unity, since it is a matter of personal preference how individuals or households allocate additional income to purchasing time savings. See also Time geography References Further reading Vickerman, R.W. 1975 The Economics of Leisure and Recreation, London:Macmillan External links Values of time and operating costs - UK Department for Transport WebTAG (Web Transport Analysis Guidance) Value of travel time savings in the UK: Summary Report - DfT-commissioned report by PJ Mackie et al., January 2003. Value of travel time savings in the UK: Full Report - DfT-commissioned report by PJ Mackie et al., January 2003. Goldszmidt, A., List, J. A., Metcalfe, R. D., Muir, I., Smith, V. K., & Wang, J. (2020). - The Value of Time in the United States: Estimates from Nationwide Natural Field Experiments (No. w28208). National Bureau of Economic Research. Transport economics