Strict CAPM treats all equities as the same kind of cash-flow claim, distinguished only by beta. For most industrial businesses that abstraction is fine — beta captures the systematic-risk variation across firms reasonably well. But four sectors — banks, insurance, REITs, and regulated utilities — have business-model features that strict CAPM systematically mis-prices, and each has evolved a sector-specific cost-of-equity convention that practitioners use instead of, or alongside, CAPM. The advanced cost-of-capital practitioner needs to know which convention applies where and why.
Equity value sits on top of a highly-leveraged balance sheet; ROE and book-value dynamics dominate cross-sectional valuation
ROE-COE spread; market-implied COE from P/B and ROE algebra
Insurance (P&C, life)
Float-driven; investment-yield duration mismatches policyholder cash-flow timing; net income is multi-year
Embedded value yields; underwriting margin plus investment yield decomposition
REITs
Mandatory 90%-of-taxable-income payout; depreciation distorts net income; reinvestment structurally constrained
FFO/AFFO yield + growth as cost-of-equity proxy
Regulated utilities
PUC sets an allowed return on rate base; allowed ROE is the regulatory ceiling and reflects regulator's view of cost of capital
Allowed ROE convention; PUC settlement data as the anchor
§ 02
The ROE-COE spread for banks is the most leverage-able relationship in advanced bank valuation. The algebra: a stable-growth bank's P/B ratio satisfies P/B = (ROE - g) / (COE - g). Rearranging, COE = ROE - (ROE - g) / (P/B) * (P/B - 1) ... but the practical shortcut is: a bank earning 14% ROE that trades at 1.6x P/B is signaling COE in the high single digits (8-10%); a bank earning 12% ROE that trades at 1.0x P/B is signaling COE roughly equal to ROE (so 12%); a bank earning 8% ROE that trades at 0.6x P/B is signaling COE WELL ABOVE ROE (so 12-14%), which is the textbook value-trap configuration. Reading the implied COE off the market is the cross-check that exposes whether your CAPM-built COE is internally consistent with how the market is actually pricing the equity.
§ 03
Bank Market-Implied COE = (ROE - g) / (P/B) + g
§ 04
Pick a regional bank under $50B in assets from **Fundamentals**. Pull its trailing ROE, its current P/B, and an approximate long-run growth rate (proxy: nominal GDP growth, ~3-4%). Solve for market-implied cost of equity using the formula above. Compare to the CAPM cost of equity that a generalist analyst would produce. The spread tells you what the market is actually pricing into this bank's equity — and which direction your CAPM-based valuation is systematically off.
§ 05
An equity REIT trades at $50/share with $5.00 of FFO/share and 3% expected long-run FFO growth. A generalist analyst applies strict CAPM with a 0.85 beta and produces a cost of equity of 8.25%. What is the FFO-yield-based cost-of-equity proxy, and how should the analyst reconcile the difference?
§ 06
Regulated utilities are the cleanest sector convention because the PUC explicitly sets the allowed ROE during each rate case. The allowed ROE is the regulatory ceiling on what the utility equity can earn on the approved rate base; the regulator's stated objective is to set the allowed ROE equal to the utility's cost of capital, so that equity investors are willing to fund the next dollar of CapEx without being subsidized. Allowed ROEs in 2024-2025 have ranged from 9.0% to 10.5% across state PUCs depending on jurisdiction, with a national median around 9.7%. The DISCIPLINED reading: use the allowed ROE as the primary cost-of-equity anchor for a regulated utility, cross-check against CAPM and a build-up estimate, and treat any large gap (>150 bps) between the methods as a flag that either the CAPM beta is mis-specified or the regulator has set the allowed ROE outside the cost-of-capital range. Regulatory lag, fuel-adjustment-clause economics, and stranded-asset risk move the actual EARNED ROE versus the allowed ROE in any given year; for forward-looking valuation, anchor to the allowed ROE and add a small premium (50-100 bps) for the gap between earned and allowed in periods of regulatory tightness.
§ 07
An analyst values a state-regulated water utility with $4B of rate base, an allowed ROE of 9.8%, and an actual trailing earned ROE of 8.6% (the gap due to regulatory lag on cost recovery). The analyst's CAPM-built cost of equity is 7.5%. The water utility is mid-cycle in a rate case that observers expect will lift the allowed ROE to 10.2%. What cost of equity should the analyst carry into the DCF, and why?
Five questions · AI feedback
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Sit with the ideas.
You are reviewing four cost-of-equity estimates produced by a generalist analyst applying strict CAPM uniformly across sectors. The estimates are: a regional bank at 9.5%, a property-casualty insurer at 9.0%, an equity REIT at 8.5%, and a regulated electric utility at 8.0%. A sector specialist objects that strict CAPM systematically misprices three of the four. Which sector-convention objection is the most disciplined?
