6 Capital Budgeting

Learn how to evaluate long-term investments using discounted cash-flow measures and practical project-selection considerations.

Evaluating long-term investments

Capital budgeting evaluates long-term investments, such as equipment, facilities, or product lines, that commit resources now in expectation of future benefits. Because cash received later is worth less than cash received today, analysis focuses on project cash flows and discounts them to account for time and risk.

Net present value

measures the present value of expected project cash inflows minus the present value of cash outflows. For an initial investment at time $0$ , it is calculated as:

\text{NPV}=-I_0+\sum_{t=1}^{n}\frac{CF_t}{(1+r)^t}

Here, $I_0$ is the initial investment, $CF_t$ is the project’s incremental cash flow in period $t$ , and $r$ is the discount rate appropriate to the project’s risk. Accept an independent project when its NPV is positive because it is expected to add value after covering the required return. For mutually exclusive alternatives, the project with the highest positive NPV generally adds the most value when the alternatives are compared on a consistent basis.

Applying the NPV rule

A machine costs $\$100{,}000$ and is expected to generate $\$45{,}000$ at the end of each of the next three years. At a discount rate of $10\%$ :

\text{NPV}=-100{,}000+\frac{45{,}000}{1.10}+\frac{45{,}000}{1.10^2}+\frac{45{,}000}{1.10^3}\approx \$11{,}908

The positive NPV indicates that the investment is expected to earn more than the required return of $10\%$ . The discount rate should reflect the opportunity cost of capital and the project’s risk. A project with materially different risk from the firm’s existing operations may require a different rate.

Internal rate of return

The is the discount rate that makes a project’s NPV equal to zero. For conventional cash flows—an initial outflow followed by inflows—accept an independent project if its IRR exceeds the required return. In the machine example, the IRR is greater than $10\%$ , consistent with the positive NPV at that rate.

IRR expresses a return as a percentage, which can be easy to communicate, but it can mislead when mutually exclusive projects differ in scale or timing. Cash flows that change direction more than once can also produce multiple or no meaningful IRRs. If NPV and IRR give conflicting rankings for mutually exclusive projects, NPV is usually the better guide to value creation.

Payback methods

The is the time required for cash inflows to recover the initial investment. With equal annual inflows, calculate it as:

\text{Payback period}=\frac{\text{Initial investment}}{\text{Annual cash inflow}}

For the machine example, payback is approximately $\$100{,}000\div\$45{,}000=2.22$ years. With uneven inflows, add cash flows period by period until the initial outlay is recovered. If recovery occurs partway through a year, estimate the fraction using that year’s cash flow.

Payback is simple and gives a rough indication of how quickly funds are recovered. Ordinary payback, however, ignores the time value of money and cash flows received after the cutoff, and it does not measure total value created. improves on one limitation by discounting cash flows before calculating recovery time, but still ignores cash flows after payback. Treat either measure as a supplementary screening tool, not a replacement for NPV.

Building realistic cash-flow estimates

Reliable project estimates focus on : include cash flows that change because the firm takes the project rather than relying on accounting profit alone. Consider effects on existing sales, costs, and other operations.

Exclude because money already spent cannot be recovered through the current decision. Include when resources used by the project—including resources the firm already owns—could instead be used elsewhere.

Estimate after-tax cash flows and include relevant investment, working-capital, and end-of-project cash flows, such as salvage value or recovery of working capital. Keep inflation assumptions consistent by using nominal cash flows with a nominal discount rate, or real cash flows with a real rate.

Test how results change when key estimates, such as sales, costs, project life, or the discount rate, change. Scenario and sensitivity analysis can show which assumptions drive the decision.

Comparing projects and making decisions

Compare mutually exclusive alternatives on a consistent basis. If projects have different useful lives, consider whether their lives can be aligned or compare equivalent annual values. When capital is limited, selecting projects may require evaluating the best feasible portfolio rather than simply choosing the project with the highest IRR.

Financial returns are not the only relevant considerations. Regulatory obligations, strategic fit, operational constraints, and environmental or social effects may matter alongside them. After implementation, compare actual results with forecasts to improve future estimates.

NPV estimates value added in currency and is generally the primary decision rule: accept positive-NPV independent projects and use NPV to rank mutually exclusive alternatives. IRR provides a percentage return but can give ambiguous or conflicting rankings. Payback highlights speed of recovery but omits important information about the time value of money and later cash flows. Sound decisions depend on realistic, risk-adjusted incremental cash-flow estimates and careful comparison of alternatives.