Choice of Discount Rate

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Many considerations enter into the selection of a discount rate. First let us consider the focus of the analysis. If the analyst employs return to all invested capital, then a discount rate appropriate to the entire capital structure should be chosen. This rate is usually called a weighted average cost of capital, because it includes costs for both debt and equity capital. In contrast, a return to equity capital focus calls for an equity-based discount rate. Following the well-known capital asset pricing model of finance, this rate includes at least two components: a risk-free rate and a risk premium, reflecting both the risks of general economic conditions and the risks of the specific business and industry. The beta β coefficient is the typical measure of risk premium used.

Next we consider adjusting for growth or inflation. When the estimates of future returns reflect inflation, then a discount rate that includes an inflation component applies. If future returns are estimated on a current (constant) dollar basis, then the inflation component should be subtracted from the discount rate. For example, suppose that an appropriate discount rate, including inflation, is determined to be 25%. The analyst uses this rate to discount estimated future returns that include inflation-based growth in revenues and costs (nominal dollars). On the other hand, if estimated future returns are based on current (constant) dollars, and the inflation assumption is 4% annually, then a discount rate of 21% (=25% minus 4% inflation adjustment) should be used to discount the current-dollar future returns. To express another way, if the future dollar amounts in the valuation analysis reflect future prices and costs, the discount rate should include the inflation component. If the future dollar amounts are based on current prices and costs, reflecting no growth or inflation, the discount rate should exclude the inflation component.

These two discounting approaches do not provide exactly the same answer, but they are close enough. Given the many assumptions that go into a valuation calculation, the slight difference is usually deemed acceptable. For example, assume that the annual cash flow is currently $300,000. An 8-year time horizon is used for the analysis. It is estimated that cash flows will grow by 5% annually. A discount rate of 15%, including growth, is deemed appropriate. The present value of $300,000 annually discounted at 10% (15% minus the 5% growth assumption) and the present value of the growth-adjusted cash flows discounted at 15% are shown in Table 11.1.

When multiyear analysis is used, a growth or inflation factor should be considered in some way. If growth is completely ignored in the above example, the present value of a $300,000 annual cash flow discounted at 15% would be approximately $1,350,000. If growth is expected, ignoring it clearly understates the value of the business. Of course, if future declines in cash flows are expected, indicating a business with initial appeal but little staying power, ignoring the expected negative growth would overstate the business value.

As seen in the above example, a positive growth assumption can either be built into the cash flow estimates, or incorporated by a reduction of the discount rate. Either approach will increase the business value relative to making no adjustment for growth.

The two present values in Table 11.1 are approximately the same, differing by 2%, which may be more precise than the cash flow estimates themselves or the discount rate selection. Nonetheless, one could easily find the precise discount rate and use that. If one accepts 10% as the correct rate without growth, then the correct rate with 5% growth that would discount the cash flows with growth (fourth column above) to the $1,600,476 present value turns out to be 15.50%. Similarly, if one accepts 15% as the correct rate with growth, then the correct rate without growth that would discount the constant cash flows (second column above) to the $1,628,604 present value turns out to be 9.52%. But for most purposes, the process illustrated above is sufficient.

Most of the literature on the weighted average cost of capital is based on information from public capital markets. Recently, work has been done to try to establish a private cost of capital approach. 1 They identify five different capital markets for private firms: bank lending, asset-based lending, mezzanine financing, private equity, and venture capital. Median rates of returns for these markets (first quarter 2010) were found to range from 6.8% for bank lending to 38.2% for venture capital financing.