When market prices on equity capital are not available, attempts to estimate cost of capital typically focus on accounting data or the identification of similar publicly traded firms. Ball and Brown (1969), Beaveret al.(1970), and many others have studied the relationship between accounting data and CAPM betas. So-called ‘‘accounting betas’’ have been calculated and compared to their market data counterparts. In a comprehensive study, Thompson (1976) found that while there is clearly a significant relationship between accounting variables and market betas, no CAPM-type model of accounting data is able to account for even as much as half of the cross-sectional variation in firm’s market betas using accounting data. Hence this line of research has been useful for testing hypotheses regarding the relationship of certain accounting variables to systematic risk, but the approaches have not been sufficiently accurate to be of practical usefulness for cost of capital estimation.