Does corporate governance matter for stock returns volatility in the Brazilian context?

Abstract

PurposeThis paper aims to examine the Brazilian stock market behavior and volatility term structure of two portfolios that, theoretically, the companies that comprise them have different degrees of idiosyncratic risk: one portfolio consists of firms with good corporate governance and the other comprises firms with poor corporate governance.Design/methodology/approachThe sample comprises corporate firms listed in the Brazilian stock market during the period from January 2008 to December 2017. Generalized autoregressive conditional heteroskedasticity models were applied.FindingsThe results show that the portfolio of firms with good corporate governance practices presents fluctuations that are more often temporary and reactive, with trends’ persistence of shorter durations, when considering the punctual volatility of the parameters estimated. This opposed expectation that the portfolio comprised of companies with good governance practices are better protected from short-term movements. However, over time and with standard error measures in consideration, both portfolios’ volatilities behave in similar ways. These findings may be related to Brazilian market characteristics, such as ownership concentration, ineffective corporate boards and the ever-developing nature of the stock market in Brazil. Any one of these characteristics present challenges to effective enforcement of the corporate governance practices in the Brazilian context.Originality/valueThe findings are potentially to the interest of researchers and practitioners for several reasons. First, this paper contributes to the growing literature on the relationship between corporate governance and market volatility. Second, it informs that volatility in the Brazilian context is likely only partially, if at all, influenced by corporate governance practices. Third, longitudinally, both indices follow the same pattern and converge to the same place.