nrior research shows that the contemporaneous linear relation between annual stock
returns and accounting earnings has declined over the past 30 years. For example,
Francis and Schipper (1999), Lev and Zarowin (1999), and Ely and Waymire (1999)
estimate regressions of annual (or 15-month) returns on the level and/or change in annual
earnings deflated by beginning market value, and they find that the slope coefficients and
R2s in these regressions decrease strongly over time.1 In this paper, we investigate two
explanations for this declining relation: (1) earnings increasingly reflect news with a lag
relative to stock prices (hereafter lags) and (2) earnings increasingly reflect good and bad
news in an asymmetric fashion (hereafter asymmetry). These explanations interact, because
if there is asymmetry with respect to the current price change, then there must be asymmetry