Compute net present value and internal rate of return for a general cash flow stream
A project has irregular cash flows over several periods and you must compute NPV at a given rate or find the IRR.
Lay the cash flows on a timeline including signs; NPV = sum over t of CF_t · v^t at the given rate. For IRR, solve NPV(i) = 0 using the CF worksheet on the BA II Plus. Watch for multiple IRRs when sign changes are non-monotonic and check uniqueness via Descartes' rule of signs.
NPV(i) = Σ CF_t / (1 + i)^t; IRR satisfies NPV = 0.