Process of quantifying costs and benefits of a decision, program, or project (over a certain period), and those of its alternatives (within the same period), in order to have a single scale of comparison for unbiased evaluation. Unlike the present value (PV) method of investment appraisal, CBA estimates the net present value (NPV) of the decision by discounting the investment and returns. Though employed mainly in financial analysis, a CBA is not limited to monetary considerations only. It often includes those environmental and social costs and benefits that can be reasonably quantified.
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