Direct Answer: How to Calculate Net Present Value
To calculate Net Present Value (NPV), you discount every future cash inflow and outflow back to today’s dollars using your chosen discount rate (hurdle rate), then subtract the initial investment cost.
The Universal NPV Formula
NPV = ∑ [ Ct / (1 + r)t ] − C0
- Ct = Net cash flow generated during period t
- r = Discount rate (rate of return or cost of capital)
- t = Time period (in years or months)
- C0 = Initial cash outlay (investment cost at Year 0)
Step-by-Step Calculation Process
- Identify Initial Outlay (Year 0): Determine the upfront capital invested or lump-sum buyout offer under evaluation. This is a negative cash flow at time zero.
- Forecast Future Cash Inflows: Project expected cash flows for each individual period (e.g., Year 1 through Year 10 or over your projected retirement longevity).
- Select an Appropriate Discount Rate: Benchmark against high-grade corporate bond yield curves, Treasury rates, or your expected portfolio return rate (typically 4.5%–6.5%).
- Calculate Present Value for Each Period: Divide each period’s cash flow by
(1 + r)t. - Sum and Subtract Initial Capital: Add all individual discounted present values together, then subtract the Year 0 initial cash outlay.
Worked Example: Calculating NPV for a Project
Suppose an investment requires an initial cash outlay of $10,000 today and is expected to pay back $3,000 each year for 4 years at a 6% discount rate (r = 0.06):
| Period | Cash Flow | Discount Factor (1 / 1.06t) | Present Value (PV) |
|---|---|---|---|
| Year 1 | $3,000 | 0.9434 | $2,830.19 |
| Year 2 | $3,000 | 0.8900 | $2,669.99 |
| Year 3 | $3,000 | 0.8396 | $2,518.86 |
| Year 4 | $3,000 | 0.7921 | $2,376.28 |
| Sum of Present Values (Gross PV) | $10,395.32 | ||
| Less Initial Investment (C0) | −$10,000.00 | ||
| Net Present Value (NPV) | +$395.32 | ||
Because the NPV is positive (+$395.32 > 0), this project creates net wealth above the 6% opportunity cost of capital.