This report on the assessment of travel time savings has been prepared by consultants (Jacobs NZ Ltd with Ian Wallis Associates Ltd) as part of the NZ Transport Agency’s 2013/14 research programme. New Zealand economic evaluation procedures rely heavily on the estimation of (generally small) time savings by many individuals, taking no account of possible variations in valuations (e.g. by extent of time savings, trip duration, level of income). It is unclear whether this is consistent with behavioural evidence or with international best practice on valuations of travel time savings (VTTS). The objective of the research was to assist decision makers by providing guidance on the strengths and weaknesses of the existing New Zealand economic evaluation methods and on alternative methods for valuing, aggregating and weighting travel time savings (including small travel time savings) to individual users. This report is structured around the following main topic areas: • The significance of travel time savings in economic appraisals. This is addressed in chapter 2. • International literature evidence and practice on how VTTS varies with trip duration (or trip length) and with the extent of time savings. This topic is summarised in chapter 3, with a detailed review of the literature and practice set out in appendices B and C. • Review and summary of earlier New Zealand research evidence on the variation of VTTS with trip length and income. This topic is summarised in chapter 4, with additional commentary in appendix D. • Findings from exploratory New Zealand-based market research undertaken in the project - which focused on respondent preferences between smaller and larger time savings per trip, and between time savings on longer compared with shorter trips. This is summarised in chapter 5, with the detailed survey specification and results given in appendix E.1 • Discussion of ‘equity’ issues and alternative approaches to treatment of income effects in the application of VTTS in project evaluation. This is the subject of chapter 6. • Selected additional issues relating to economic appraisal methods and their application. These are covered in chapter 7.2 • The report concludes with chapters summarising our conclusions and recommendations (chapter 8) and providing a full list of references (chapter 9). (Author/publisher)
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