When to use it
Use it when evaluating financial options with explicit timing, a suitable discount rate and defensible cash-flow estimates.
Do not treat positive NPV as proof that a project is affordable, strategically suitable or free of risk.
- Define the scope, status date and units before collecting the inputs.
- Substitute the values into the formula and retain their units.
- Interpret the result against the assumptions and decide what evidence or action is needed next.
Formula & inputs
CFₜ is a signed net cash flow at period t. The rate r uses the same period; the initial cash flow occurs at t = 0.
Worked example
An illustrative project requires €100,000 now and produces €40,000 at each of the next three year ends. The assumed annual discount rate is 10%.
The present value is slightly negative under these assumptions. Test the cash flows and rate rather than treating the result as certain.
Common pitfall
Mixing nominal cash flows with a real discount rate, omitting later costs or discounting the initial outlay again distorts the result.
Source & related material
Standard quantitative technique; this explanation is by fannarmaximus. No single inventor is claimed. The arithmetic is computed from explicit inputs, not copied from an official sample question.