Board Gender Diversity and Firm Performance: An Analysis of the Causal Relationship in Spanish Listed Companies

Applying a mixed theoretical approach, this paper addresses the causal relationship between the presence of women on steering committees (SC) and in senior management positions and the firm’s stock return, measured through the price–earnings ratio (P/E). To do so, we disaggregate the composition of the boards of 27 IBEX 35 companies over the period 2018–2021 by gender and type of female director and analyze the relationship between the number and proportion of women on the SC, their distribution by category, and the P/E. The sample contains a total of 108 observations, and its structure follows a panel data methodology. Validation of the working hypotheses was carried out using Poisson logistic regression. The results indicate a positive and significant relationship between stock returns and the percentage of women on the SC. The results also indicate that stock returns are not significantly affected by the category distribution of female directors.