Definition
Net present value is the sum of the present values of all cash flows associated with a decision, treating outflows as negative and inflows as positive, and expressed as a single figure at the moment the decision is made.
Why it matters
Many decisions in retirement income involve trading a payment today for a stream of receipts over time; whether the trade is worthwhile depends on comparing the two on a common basis. Net present value provides that basis by placing every associated cash flow at the same reference point. A positive net present value indicates the receipts, discounted to today, exceed the payment; a negative net present value indicates the opposite.
How it works
Net present value is the sum of each cash flow, discounted from the date it occurs back to today at the chosen discount rate. Consider an individual paying $500,000 today for a lifetime income arrangement expected to deliver $30,000 per year over a 20-year receipt period, evaluated at a 3 percent discount rate. The present value of the income stream is about $446,300, and the present value of the payment is negative $500,000, giving a net present value of approximately negative $53,700 at those parameters. Whether this indicates an unfavorable trade requires context: if the arrangement also provides longevity protection that a bare present-value comparison does not capture, the net present value figure understates its value; if the individual would have discounted at a higher rate, the figure would be more negative. Net present value is a mechanical output; interpretation requires knowing what has been included and excluded from the cash flow list.
In practice
For an individual evaluating a lifetime income arrangement against a premium paid today, net present value is a starting point rather than a conclusion. The mechanical figure answers the narrow question of whether the discounted income stream exceeds the premium under the assumed discount rate and expected receipt period; it does not capture longevity insurance value, which is the actual point of the arrangement for most individuals. A professional will typically produce a net present value figure alongside an actuarial present value that incorporates survival probability, and then present both. Individuals should ask what discount rate has been used, what receipt period has been assumed, and whether survival weighting has been applied, before treating a net present value figure as decisive.
Related terms
- Present value
- Actuarial present value
- Discount rate
- Internal rate of return
- Break-even analysis (annuity context)
- Cost of income
- Realized value