Cost of equity estimation for the Brazilian market: a test of the Goldman Sachs model

Abstract

As an approach to determining the degree of integration of the Brazilian economy, this paper seeks to test the explanatory power of the Goldman Sachs Model for the expected returns by a foreign investor in the Brazilian market during the past eleven years (2004-2014). Using data for the stocks of 57 of the most actively traded firms at the BM&FBovespa, it begins by testing directly the degree of integration of the Brazilian economy during this period, in an attempt to better understand the context in which the model has been used. In sequence, in an indirect test of the Goldman Sachs model, the risk factor betas (market risk and country risk) of the sample stocks were estimated and a panel regression of expected stock returns on these betas was performed. It was found that country risk is not a statistically significant explanation of expected returns, indicating that it is being added in an ad hoc fashion by market practitioners to their cost of equity calculations. Thus, although there is evidence of a positive and significant relationship between systematic risk and return, the results for country risk demonstrate that the Goldman Sachs Model was not a satisfactory explanation of expected returns in the Brazilian market in the past eleven years, leading us to question the validity of its application in practice. By adding a size premium factor to the model, there is evidence of a negative and significant relationship between companies’ size and return, although country risk remains not satisfactory to explain stock expected returns.