This paper reconstructs a monthly Brazilian retirement-return panel from January 1968 through August 2026 and estimates historically sustainable fixed real withdrawal rates. The panel combines the Ibovespa gross total return equity index with Caderneta de Poupança as a conservative asset. IGP-DI is the baseline deflator for the full sample; IPCA is used from 1980 onward. Across complete monthly cohorts, maximum 30, 40, and 50-year safe withdrawal rates on a 10pp grid are 3.71%, 3.27%, and 2.98%. Annual replication of Bengen (1994) gives 3.43% for 50% Ibovespa / 50% Poupança. On Bengen's 25-point grid the peak is 3.98% at 25% / 75%. A 48-month moving-block bootstrap with 50,000 paths yields 95%-success maxima of 2.42%, 1.84%, and 1.51%.