Firm Size and the Information Content of Financial Statements

The Capital Asset Pricing Model has been challenged recently by several studies that point to certain anomalies in the capital market related to firm size. Banz 3 reported a nonlinear relation between the aggregate market value of a firm's common stock and the stock's mean return. He found that firms with small market values had large and positive residual returns over a period of at least 40 years. Reinganum 23 found that high earning-price (E/P) stocks had higher returns than low E/P-ratio stocks and that, after controlling for size, the E/P effect largely disappeared. Although they rejected the hypothesis that the anomalies are due to inefficiency in the capital market, the two authors are not able to identify the economic factors that might explain the effect of firm size on the functioning of the capital market.