Presidential Elections and Stock Returns of Brazilian State-Linked Firms From 1998 to 2022

This study describes stock returns around seven Brazilian presidential elections from 1998 to 2022 for Banco do Brasil, BB Seguridade, Caixa Seguridade, Eletrobras, Telebras, and Petrobras. Five windows surrounding the first round are examined using cumulative abnormal returns calculated as the sum of daily returns in excess of a fixed, historically calibrated CAPM-style benchmark. The unbalanced panel provides 154 complete firm-window observations out of 210 potential combinations. Analytical tests of zero CAR use a first-order forecast variance with Bartlett-weighted autocovariances and a normal approximation. Of 142 tested CARs, 15 have nominal p-values below .05; three remain significant after Holm adjustment at the 10% level. The analysis does not identify causal election effects. In 2018, all five observed firms have positive values in both post-election windows. In 2022, four of six firms have positive values at four weeks, while only two of the five firms with complete data have positive values at thirteen weeks. The results document differences across firms and horizons, subject to benchmark sensitivity, overlapping windows, and incomplete historical coverage. The study provides longitudinal evidence on firm-specific election-period returns in Brazil.