The Duration of Excess Returns Is the Underappreciated Value Driver
A Research Note on the Competitive Advantage Period and its role in long-term business analysis.
Two companies can generate identical returns on capital and yet command fundamentally different valuations. The distinguishing factor is often not the level of those returns, but the length of time over which they can be sustained. In a discounted cash flow valuation, a substantial portion of enterprise value is typically derived from the terminal value, which in turn depends on the duration for which a company can continue to earn returns above its cost of capital. Despite its importance, this duration is rarely assessed explicitly, even though it often has a greater impact on intrinsic value than any individual annual forecast.
Competitive Advantage Period
The concept of the Competitive Advantage Period (CAP) was introduced by Michael Mauboussin and Paul Johnson in 1997, building on Alfred Rappaport's earlier concept of Value Growth Duration. Its central premise is straightforward: a company creates economic value only for as long as it earns returns on capital in excess of its cost of capital. The CAP therefore represents the period over which this value-creating spread between return on invested capital (ROIC) and the cost of capital can be sustained. As competitive forces erode excess returns over time, ROIC converges toward the cost of capital, and incremental growth ceases to create additional shareholder value.
Unlike revenue growth or operating margins, the CAP cannot be observed directly in the financial statements. It is an implicit assumption embedded in every valuation, yet it is rarely stated explicitly. Any assessment that concludes a company's current share price reflects intrinsic value also implicitly assumes a particular duration of competitive advantage, whether that assumption is made explicitly or not.
The Convergence of Returns
The economic mechanism underlying the CAP is competition. Returns on capital in excess of the cost of capital create economic profits that attract both new entrants and additional investment. As competitors replicate successful business models and competitive intensity increases, pricing power and margins come under pressure. Over time, returns on capital converge toward the cost of capital, a process commonly described in the literature as fade or convergence.
The pace of this adjustment is referred to as the fade rate and is inversely related to the CAP. A high fade rate implies that excess returns are competed away quickly, whereas a low fade rate indicates a more durable competitive advantage. Crucially, the speed of convergence depends not on the magnitude of current returns, but on the strength and durability of the competitive advantages that protect them. A business generating moderate but well-defended returns may therefore possess a longer CAP than one earning exceptionally high returns that lack structural protection.
The level of excess returns and the duration over which they can be sustained are distinct analytical variables and should be assessed independently.
A Concept, Not a Metric
A common misconception is to treat the CAP as an observable metric. It is not. The CAP is an analytical estimate rather than a directly measurable quantity. While historical data can be used to estimate average fade rates, those averages mask substantial variation across industries, business models, and individual companies.
A second misconception is to assume that a long history of excess returns necessarily implies a long future. Technological disruption, regulatory change, or new competitive entrants can materially shorten a competitive advantage that has persisted for many years. The CAP should therefore be viewed not as a permanent attribute of a business, but as an analytical assessment that requires continuous reassessment as competitive conditions evolve.
Finally, the concept can create an unwarranted impression of precision. Estimating a range of plausible outcomes is generally more appropriate than assigning a single point estimate. The primary analytical value of the CAP lies not in predicting an exact number of years, but in explicitly assessing the expected durability of a company's competitive advantage. A well-reasoned range is therefore more informative than a falsely precise estimate.
Where Most Companies Sit
Counterpoint Global's 2026 update provides an empirical perspective on the concept. Across a broad sample of U.S. companies, observed fade rates are concentrated between 0.10 and 0.30, with an average of approximately 0.21. This corresponds to a typical CAP of roughly five to twenty years.
Two implications are particularly relevant for fundamental analysis. First, for most companies, a substantial portion of intrinsic value is created over a period that extends well beyond the explicit forecast horizon typically used in valuation models. As a result, assumptions regarding the duration of excess returns often have a greater influence on intrinsic value than changes to near-term financial forecasts.
Second, the Competitive Advantage Period is most informative for businesses in the growth and maturity phases of their life cycle, where the majority of publicly listed companies have historically been concentrated. By contrast, the concept is less informative for very early-stage businesses, where sustainable returns on capital have yet to emerge, and for structurally declining businesses, where competitive advantages have already begun to erode.
Conclusion
The level of a company's return on capital can be observed directly from its financial statements. The durability of those returns, by contrast, is a matter of analytical judgment. Any valuation therefore contains an implicit assumption about the length of time a company can sustain returns above its cost of capital. Making that assumption explicit is analytically more robust than leaving it embedded within the terminal value.
The CAP does not provide a precise answer to this question. Rather, it provides a disciplined analytical framework for assessing how long a company's competitive advantages can realistically be sustained. Framing that question explicitly is not a secondary aspect of valuation, it is one of its central judgments.
What This Means for Accelith Value Select
For Accelith Value Select, the CAP does not introduce an additional valuation technique. Rather, it provides a more disciplined framework for assessing competitive advantage. At its core, the question of whether a competitive advantage is durable is ultimately a question of how long it can be sustained.
The analytical value of the concept lies in separating two distinct questions that are often considered together: the level of a company's current returns on capital and the expected duration of those returns. A business generating exceptional returns that cannot be supported by durable competitive advantages does not pass the competitive advantage assessment, regardless of how attractive its current financial metrics may appear.
The CAP is therefore less an additional step in the analytical process than a framework for distinguishing the magnitude of excess returns from their expected persistence.
Academic References
- Damodaran, Aswath. Investment Valuation: Tools and Techniques for Determining the Value of Any Asset. 3rd ed. Hoboken, NJ: Wiley, 2012.
- Mauboussin, Michael J., and Paul Johnson. "Competitive Advantage Period 'CAP': The Neglected Value Driver." Financial Management 26, no. 2 (1997): 67-74.
- Rappaport, Alfred. Creating Shareholder Value: The New Standard for Business Performance. New York: Free Press, 1986.
Practitioner References
- Holland, David A., and Bryant A. Matthews. Beyond Earnings: Applying the HOLT CFROI and Economic Profit Framework. Hoboken, NJ: Wiley, 2018.
- Mauboussin, Michael J., and Dan Callahan. "Competitive Advantage Period: The Neglected Value Driver." Consilient Observer, Counterpoint Global Insights, Morgan Stanley Investment Management, April 14, 2026.