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The Economic Evaluation of Transport Projects Seminar Madrid, 15-16 November 2010. Current debates on the cost-benefit analysis of transport projects in Great Britain. Chris Nash Institute for Transport Studies University of Leeds. Outline. Introduction
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The Economic Evaluation of Transport ProjectsSeminarMadrid, 15-16 November 2010 Current debates on the cost-benefit analysis of transport projects in Great Britain. Chris Nash Institute for Transport Studies University of Leeds
Outline • Introduction • Current British Approach to Transport Appraisal • Optimism Bias • Value of Time • Wider Economic Benefits • Accessibility • Decision criteria • Distribution of costs and benefits • Conclusions
New Approach to Transport Appraisal (NATA) 1998 To be applied to all decisions: • Road investment • Public transport investment • Subsidies Move to 3.5% discount rate and 60 year time horizon
NATA objectives Environment Economy Safety Accessibility Integration Note. DASTS (2008) replaces accessibility with equality of opportunity and abandons integration
Transport Economic Efficiency Table User Benefits (time, operating costs, user charges, delays during construction) Private Sector Provider Impact (revenues, costs, grants and subsidies) Other Impacts Net Business Impact Total
Public Accounts Table Local Government Funding Central Government Funding (inc. impact on tax revenues) Total
Monetarised Costs and Benefits Table (adds in) Noise Local air quality Greenhouse gases Journey ambience Reliability Interchanges Option Values
Appraisal summary table Environment Noise Local Air Quality Greenhouse Gases Landscape Townscape Heritage of Historic Resources Biodiversity Water Environment Physical Fitness Journey Ambience
Appraisal summary table CTD Safety Accidents Security Economy Public Accounts Transport Economic Efficiency Reliability Wider Economic Impacts Accessibility Option values Severance Access to the Transport System Integration Transport Interchange Land-Use Policy Other Government Policies
Valuation of costs and benefits – key issues • Optimism bias • Value of time (esp business travel and small time savings) • Wider Economic Benefits • Accessibility • Decision Criterion • Distribution
Risk and OptimismBias Adjustments for Capital Expenditure Source: WEBTAG
Value of Time Savings for rail Passengers in the UK Source: DfT: WEBTAG Unit 3.5.6 (www.webtag.org)
Wider economic benefitsfrom generated traffic Causes? Agglomeration externalities Imperfect competition in output markets Labour supply Magnitude up to 30% of direct benefits?
Crossrail CBA (£mPV) Time savings 12832 Crowding 2889 Other transport benefits 372 Wider economic benefits 7161 Total benefits 23254 Total costs 13902 Less revenues -6149 Plus tax loss 1207 Cost to government 8960 BCR 2.6 (1.8 excl Wider economic benefits)
Draft WebTAG guideline Option values for commuter services
Decision Criterion and Value for Money NB Negative costs and positive benefits implies high value for money
Treatment of distribution Need to forecast final impact of costs and benefits (note - they may be passed on through land prices, wage rates, prices of goods in shops) Then apply weighting system NB Jubilee line extension to Docklands raised property values by £1.5b!
Quantitative Significance of Possible Weighting Systems Weights relative to mean income i.e. wi may just reflect differences in MUy or may reflect this and equity weights
Conclusions British transport appraisal is state of the art BUT • Problem of estimating costs • Still concerns about value of time • Uncertainty over wider economic benefits • Treatment of accessibility • Issue over capital rationing • Inadequate treatment of distribution • General treatment of uncertainty and robustness