Forecasts of Economic Growth from the Bond and Stock Markets Author(S): Campbell R
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Forecasts of Economic Growth from the Bond and Stock Markets Author(s): Campbell R. Harvey Source: Financial Analysts Journal, Vol. 45, No. 5 (Sep. - Oct., 1989), pp. 38-45 Published by: {cfa} Stable URL: https://www.jstor.org/stable/4479257 Accessed: 05-05-2019 02:53 UTC JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at https://about.jstor.org/terms is collaborating with JSTOR to digitize, preserve and extend access to Financial Analysts Journal This content downloaded from 24.240.33.116 on Sun, 05 May 2019 02:53:15 UTC All use subject to https://about.jstor.org/terms by Campbell R. Harvey Forecasts of Economic Growth from the Bond and Stock Markets Although both stock and bond market data contain information relevant for predicting GNP growth, the bond market delivers more accurate predictions. While yield curve measures are able to explain more than 30 per cent of the variation in economic growth over the 1953-89 period, stock market variables explain only about 5 per cent. Furthermore, forecasts based on the yield curve compare favorably with forecasts from leading econometric models, whereas forecasts from stock market models do not. Inasmuch as firms' earnings are positively correlated with economic growth, one might expect that stock prices would contain information about real economic activity. But variations in stock prices can reflect both changes in expected economic growth and changes in the perceived risk of stock cash flows. Investors' changing perceptions about the riskiness of cash flows can confound the information about expected economic growth. A yield-based forecast for the third quarter of 1989 through the third quarter of 1990 suggests a slowing of economic growth, but not zero or negative growth. T HE LINK BETWEEN ASSET markets and Similarly, the price of a share of stock is the real economic growth was formalized by discounted value of expected cash flows. The Irving Fisher.1 Fisher suggested that, in strength of the economy determines the magni- equilibrium, the one-year interest rate reflects tude of these cash flows. The price of equity the marginal value of income today in relation to thus reflects expectations of real activity, and its marginal value next year. The intuition is changes in the value of equity partially reflect straightforward. If a recession is expected next revisions in these expectations. year, there is an incentive to sacrifice today to This article measures the relevant information buy a one-year bond that pays off in the bad contained in the bond market and the stock times. The demand for the bond will bid up its market for forecasting real economic activity. price and lower its yield. The theory implies that Traditionally, the stock market is assumed to current real interest rates contain information contain important information about the future about expected economic growth. path of economic growth. The Standard & Poor's 500 stock price index (S&P 500) carries an important weight in the Department of Com- 1. Footnotes appear at end of article. merce's widely quoted index of leading indica- Campbell Harvey is Assistant Professor of Finance at Duke tors. Indeed, many forecasters predicted a re- University's Fuqua School of Business. cession for 1988 solely on the basis of the stock The author thanks Eugene Fama, Douglas Foster, Jill market crash in October 1987. The results pre- Fox, Leonard Silk and Robert Whaley for their helpful sented here suggest that the bond market re- suggestions. veals more information about future economic This article is based on a working paper by the author, "Yield Spreads, Stock Returns and Real Activity." Re- growth than the stock market. The bond market search for this paper was sponsored by a summer grant inforecasts also compare favorably with the pre- 1984 from the Center for Research in Security Prices at thedictions of seven major econometric forecasting University of Chicago. services. FINANCIAL ANALYSTS JOURNAL / SEPTEMBER-OCTOBER 1989 O 38 This content downloaded from 24.240.33.116 on Sun, 05 May 2019 02:53:15 UTC All use subject to https://about.jstor.org/terms The Bond Market and Economic Growth X Expected Dividendst + j Modern asset pricing theories suggest a relation Stock Pricet = (1) between expected asset returns and investors' = 1 (1 +kY expected consumption plans.2 The underlying where k is the rate at which (risky) dividends are idea is that investors get more benefit from one discounted. It is usually assumed that k is dollar in a recession (when their consumption constant.8 levels are low) than from one dollar at the peak Recession means lower earnings and divi- of the business cycle (when their consumption dends for most equities. If investors make a is high). As a result, in good times people tend downward revision in their forecast of a firm's to invest in assets that will provide insurance, or earnings (or dividends) because they expect a a hedge, against an expected downturn in the recession, stock price, according to the above economy. The payoffs from these investments equation, will drop. Of course, a change in are designed to smooth consumption. equity valuation could also be caused by a Investment in a zero-coupon bond provides change in the discount rate. This may confound one example of trading consumption today for the information about real growth contained in consumption in the future. The intensity at stock returns. which people are trading today's consumption Although most agree that the stock market is for tomorrow's consumption is called the mar- an important indicator, its reliability has re- ginal rate of substitution. This rate of substitution cently been questioned. Some skepticism un- is driven by expectations about the state of the doubtedly stems from the strong economic economy (business cycle) and is reflected in growth in 1988, following the stock market asset prices.3 crash. A popular joke is that the stock market Consider the link between the rate of substi- correctly forecast nine of the last four recessions.9 tution and asset prices. If there is a growing Of course, an incorrect forecast of a recession is consensus of an economic downturn, investors no joke; it is important to assess the reliability of will want to buy long-term zero-coupon bonds the stock market as an economic indicator. and sell short-term bonds. Obviously, not ev- erybody can buy long term and sell short term. A Forecasting Model In order to make the other side of the market A version of the consumption-based asset pric- attractive, the price of the long-term bonds must ing model suggests a simple linear relation rise and the price of the short-term bonds fall. In between asset returns and the marginal rate of terms of yields to maturity, the yield curve will substitution. Many have explored this relation become flatter, or invert. using real personal consumption growth as a Asset pricing theory suggests that the slope of proxy for the marginal rate of substitution. The the yield curve may contain information about growth rate in real GNP could also be consid- investors' forecasts of economic growth.4 In- ered a proxy for unobservable consumption. In deed, the yield curve (measured as the differ- terms of yields to maturity, we can estimate this ence between a 10-year and a three-month as follows:10 yield) inverted in 1969, 1973, 1979 and 1981. These inversions preceded the last four reces- Growtht + lt + 5 = a + b(Yield Spread)t + ut + 5, (2) sions.5 where The Stock Market and Economic Growth Growth = growth in real (annual) GNP There is widespread agreement that the stock from quarter t + 1 to quarter market contains important information about t + 5, real economic activity. The Department of Com- Yield Spread = spread between long-term and short-term annualized merce includes the S&P composite as one of its yields to maturity observed 12 leading indicators of economic growth.6 at time t, Many empirical studies have measured the co- movement of stock returns and real economic u = an unanticipated result (re- activity.7 sidual) and a and b = fitted coefficients. The association between stock market and real activity originates with the fundamental The model suggests that b is the average risk valuation of equity: tolerance in the economy and a the average FINANCIAL ANALYSTS JOURNAL / SEPTEMBER-OCTOBER 1989 O 39 This content downloaded from 24.240.33.116 on Sun, 05 May 2019 02:53:15 UTC All use subject to https://about.jstor.org/terms Figure A Annual GNP Growth and Lagged Five-Year Yield Spread 0.08 - 0.07 GNP Growth 0.06- 0.052 0.04 0.03- 0.02 5 58 66788 0.00 m - 0.01 -0.02 -Yield Spread - 0.03- - 0. 04 . .L.. 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 Year annual real economic growth when the term are also patterns in the returns that suggest that structure has a slope of zero. This is the model stocks lead GNP. However, the stock return used to forecast real economic growth. series are more volatile and have many more The forecasting model is evaluated using two false signals than the yield curve measures.