Idiosyncratic Consumption Risk and the Cross-Section of Asset Returns

Abstract

This paper investigates the importance of idiosyncratic consumption risk for the cross-sectional variation in average returns on stocks and bonds. If idiosyncratic consumption risk is not priced, the only pricing factor in a multiperiod economy is the rate of aggregate consumption growth. We offer evidence that the cross-sectional variance of consumption growth is also a priced factor. This demonstrates that consumers are not fully insured against idiosyncratic consumption risk, and that asset returns reflect their attempts to reduce their exposure to this risk. We find that over the sample period the resulting two-factor consumption-based asset pricing model significantly outperforms the CAPM. The model's empirical performance also compares favorably with that of the Fama-French three-factor model. Moreover, in the presence of the market factor and the size and book-to-market factors, the two consumption based factors retain explanatory power. Together with the results of Lettau and Ludvigson (2000), these findings indicate that consumption-based asset pricing is relevant for explaining the cross-section of asset returns.