ABSTRACT
Investment in rail systems has often been justified not only on the basis of strict benefit cost analysis, but also by the broader employment and development benefits. In fact, many investment decisions would not have been made if only the transport benefits had been considered. For example, the Jubilee Line extension in London had a transport benefit-cost ratio of less than one (0.95:1 in 1991 prices assuming an 8 per cent discount rate over 30 years), when benefit-cost ratios would be over 1.3 to 1 for investment to take place. This means that over 34 per cent of the benefits would be non-transport based and related to new employment and local inward investment (London Transport 1993). These additional benefits are very difficult to measure prior to the investment decision and it is only through careful modelling or retrospective analysis that we can attempt a systematic review.
