Women on corporate boards and firm's financial performance

The European Commission has proposed that member countries develop their national self-regulation and governance initiatives to increase the number of women on corporate boards with the aim of promoting gender equality in the processes of decision-making. This has provoked some controversial opinions, which in turn has led to the search for factual data which may support the legal initiatives. In order to shed more light on this topic, this study investigates the influence of a higher percentage of women on the board of directors of companies (excluding financial companies) included in the index of the Spanish Stock Exchange IBEX35 for a fifteen-year period: 2003-2017. To do this, we use a two-stage instrumental variables (IV) regression to address endogeneity and reverse causality problems. Moreover, we study the influence of a mandatory law on female presence on company boards by using a panel data methodology. The findings of this study show that the increasing number of women on boards is positively related to higher financial performance. Moreover, as expected, the gender mandatory law boosts the female proportion on boards of directors. Consequently, there are valid business as well as ethical arguments to support mandatory gender legislation.