Equity Risk Premiums (ERP): Determinants, Estimation and Implications – the 2017 Edition Updated: March 2017
Total Page:16
File Type:pdf, Size:1020Kb
Equity Risk Premiums (ERP): Determinants, Estimation and Implications – The 2017 Edition Updated: March 2017 Aswath Damodaran Stern School of Business [email protected] Electronic copy available at: https://ssrn.com/abstract=2947861 2 Equity Risk Premiums (ERP): Determinants, Estimation and Implications – The 2017 Edition The equity risk premium is the price of risk in equity markets and is a key input in estimating costs of equity and capital in both corporate finance and valuation. Given its importance, it is surprising how haphazard the estimation of equity risk premiums remains in practice. We begin this paper by looking at the economic determinants of equity risk premiums, including investor risk aversion, information uncertainty and perceptions of macroeconomic risk. In the standard approach to estimating the equity risk premium, historical returns are used, with the difference in annual returns on stocks versus bonds, over a long period, comprising the expected risk premium. We note the limitations of this approach, even in markets like the United States, which have long periods of historical data available, and its complete failure in emerging markets, where the historical data tends to be limited and volatile. We look at two other approaches to estimating equity risk premiums – the survey approach, where investors and managers are asked to assess the risk premium and the implied approach, where a forward-looking estimate of the premium is estimated using either current equity prices or risk premiums in non-equity markets. In the next section, we look at the relationship between the equity risk premium and risk premiums in the bond market (default spreads) and in real estate (cap rates) and how that relationship can be mined to generated expected equity risk premiums. We close the paper by examining why different approaches yield different values for the equity risk premium, and how to choose the “right” number to use in analysis. Electronic copy available at: https://ssrn.com/abstract=2947861 3 Equity Risk Premiums: Importance and Determinants ............................................. 5 Why does the equity risk premium matter? ............................................................................ 5 A Price for Risk ................................................................................................................................................. 6 Expected Returns and Discount Rates ................................................................................................... 6 Investment and Policy Implications ........................................................................................................ 8 Market Timing and Risk Premiums ......................................................................................................... 9 What are the determinants of equity risk premiums? ....................................................... 10 Risk Aversion and Consumption Preferences ................................................................................. 10 Economic Risk ............................................................................................................................................... 11 Information ..................................................................................................................................................... 14 Liquidity and Fund Flows ......................................................................................................................... 15 Catastrophic Risk ......................................................................................................................................... 16 Government Policy ...................................................................................................................................... 18 Monetary Policy ............................................................................................................................................ 19 The behavioral/ irrational component ............................................................................................... 20 The Equity Risk Premium Puzzle .............................................................................................. 21 Estimation Approaches ...................................................................................................... 24 Survey Premiums ............................................................................................................................ 24 Investors .......................................................................................................................................................... 24 Managers .......................................................................................................................................................... 27 Academics ........................................................................................................................................................ 28 Historical Premiums ...................................................................................................................... 30 Estimation Questions and Consequences .......................................................................................... 30 Estimates for the United States .............................................................................................................. 35 Pre-tax or Post-tax risk premium? ....................................................................................................... 38 Global Estimates ........................................................................................................................................... 40 The survivor bias .......................................................................................................................................... 41 Decomposing the historical equity risk premium ......................................................................... 44 Historical Premium Plus .............................................................................................................. 45 Small cap and other risk premiums ..................................................................................................... 46 Country Risk Premiums ............................................................................................................................ 52 Implied Equity Premiums ............................................................................................................ 79 1. DCF Model Based Premiums .............................................................................................................. 79 2. Default Spread Based Equity Risk Premiums ........................................................................... 112 3. Option Pricing Model based Equity Risk Premium ................................................................ 116 Choosing an Equity Risk Premium ................................................................................ 119 Why do the approaches yield different values? ................................................................. 119 Which approach is the “best” approach? ............................................................................. 121 Five myths about equity risk premiums .............................................................................. 124 Summary ............................................................................................................................... 126 Appendix 1: Historical Returns on Stocks, Bonds and Bills – United States ..................... 127 Appendix 2: Sovereign Ratings by Country- January 2016 ..................................................... 130 Appendix 3: Country Risk Scores from the PRS Group – January 2017 ............................. 132 Appendix 4: Equity Market volatility, relative to S&P 500: Total Equity Risk Premiums and Country Risk Premiums (Weekly returns from 1/14 – 1/16) ....................................... 134 Appendix 5: Equity Market Volatility versus Bond Market/CDS volatility- January 2017 ............................................................................................................................................................................ 137 Appendix 6: Year-end Implied Equity Risk Premiums: 1961-2015 ..................................... 140 4 5 The notion that risk matters, and that riskier investments should have higher expected returns than safer investments, to be considered good investments, is intuitive and central to risk and return models in finance. Thus, the expected return on any investment can be written as the sum of the riskfree rate and a risk premium to compensate for the risk. The disagreement, in both theoretical and practical terms, remains on how to measure the risk in an investment, and how to convert the risk measure into an expected return that compensates for risk. A central number in this debate is the premium that investors demand for investing in the ‘average risk’ equity investment (or for investing in equities as a class), i.e., the equity risk premium. In this paper, we begin by examining competing risk and return models in finance and the role played by equity risk premiums in each of them. We argue that equity risk premiums are central components in every one of these models and consider what the determinants of these premiums might be. We follow up by looking at three approaches