2.7 Time frame
- 2.1 Overview
- 2.2 Social cost benefit analysis and financial analysis
- 2.3 Benefits
- 2.4 External impacts
- 2.5 Costs
- 2.6 Present value and discounting
- 2.7 Time frame
- 2.8 Do minimum and benefit and cost differentials
- 2.9 Benefit cost ratios
- 2.10 Incremental cost benefit analysis
- 2.11 First-year rate of return
- 2.12 Uncertainty and risk
- 2.13 Alternatives and options
- 2.14 Packages
- 2.15 Transport models
- 2.16 Other inputs to funding allocation process
- 2.17 References
2.7 Time frame
Time zero
Time zero (the date all benefits and costs shall be discounted to) is 1 July of the financial year in which the project is submitted for a commitment to funding. For example, if a project is submitted for a commitment to funding in the 2007/08 National Land Transport Programme (NLTP), time zero is 1 July 2007. All project options shall use the same time zero for evaluation, irrespective of whether construction for all options would commence at that time
In the case of projects being resubmitted in subsequent years, the evaluation shall be revised to the time zero appropriate to the year for which the project is being submitted for a commitment to funding.
Analysis period
The time period used in economic evaluation shall be sufficient to cover all costs and benefits that are significant in present value terms.
The analysis period for road projects is described in section 3.7 of this volume and for transport demand management, transport services and other projects in volume 2
Base date for costs and benefits
The base date for dollar values of project benefits and costs shall be 1 July of the financial year in which the evaluation is prepared. In the case of a project being resubmitted in subsequent years, all dollar values of benefits and costs shall be adjusted to the same base date
Factors for updating construction, maintenance and user benefits are given in appendix A12. Where land costs are significant, the most recent possible estimate shall be used.
The base date for project benefits and costs need not coincide with time zero. Generally, the base date for dollar values will be one year earlier than time zero.
