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Economic Appraisal Tool
The Economic Appraisal Tool performs an economic
appraisal of a specific countermeasure or several alternative countermeasures
for a specific site. Default construction cost estimates for candidate
improvements are provided within this tool, but the user has
the capability to modify the default estimates based on local experience.
The user has the option to select the type of economic appraisal
to be performed: cost effectiveness (countermeasure cost per accident
reduced), benefit-cost ratio (ratio of monetary benefits to countermeasure
costs), or net present value (excess of monetary benefits over countermeasure
costs). Safety effectiveness measures (i.e., benefits) are estimated
from data on the observed, expected, and predicted accident frequency
and severity at the site; the accident patterns identified in the preceding
tools; and accident modification factors (AMFs) for specific countermeasures.
The AMFs representing the safety effectiveness of particular countermeasures
are based on the best available safety research. The analyses include appropriate consideration of the service life of the countermeasure
and the time value of money. This tool can perform economic
analyses consistent with the requirements of the Federal Highway Safety
Improvement Program (HSIP) so that analysis results will be readily acceptable
to FHWA for implementation with Federal funds.
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