- What's the difference between PV and NPV?
- PV calculates present value of regular, equal payments over time at a constant rate. NPV adds present values of irregular cash flows that occur at specific times. Use NPV when payment amounts or intervals vary.
- Should I use negative or positive values for pmt?
- Use negative for cash you pay out (expenses, loan payments, storage costs) and positive for cash you receive (dividends, supplier rebates). The sign of pmt determines the sign of the result—negative payments yield negative PV.
- How do I choose the right discount rate?
- The rate represents your cost of capital, inflation, or expected return. For inventory holding, use your weighted average cost of capital. For financing decisions, use the loan or credit rate. For future costs, use inflation expectations.
- Can I use PV for supply chain scenarios beyond financing?
- Yes. PV works for any series of regular amounts in the future: maintenance costs, subscription fees, lease payments, warehouse holding costs, or recurring supplier contracts. Convert annual costs to the matching period (monthly, quarterly) and adjust the rate accordingly.