Cost analyses 4:1 accident ratio

Direct and indirect costs are addressed in that report. Its Table 3 is titled Analysis of Accident Costs. Excerpts follow. Note that the ratio of indirect to direct costs diminishes as the cost of the benefits paid increases. Also, keep in mind that money numbers are in 1982 dollars. 

Analysis of the compiled data showed that the indirect cost ratio is affected by many variables. However, the report said Still, if the accident data are separated into two general groups, large and small claims, it can be seen that smaller accidents have a larger [indirect-to-direct cost] multiplier. ... 

The cost-benefit analysis including behavioural adaptation therefore included three types of benefit (1) accident reduction, (2) travel time saving, and (3) new trips in darkness. In the cost-benefit analysis not including behavioural adaptation, accident reduction was the only benefit. Figure 20.1 shows the estimated benefit-cost ratio of providing road lighting as a function of traffic volume in the two analyses. 

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