Index Fund Drawdown

Assumes a steady return every year, monthly investments compounding monthly, withdrawals taken at the start of each year, and no taxes or fund fees. Real markets vary year to year, and a few bad years early on can drain a portfolio faster than this shows. This is an estimate, not financial advice.

Historical and Monte Carlo modes use actual yearly S&P 500 total returns, 10-year Treasury bond returns and CPI inflation for 1928–2025, from Aswath Damodaran, NYU Stern. Historical runs every complete stretch of years in that record; Monte Carlo draws 1,000 random sequences of whole years from it. All amounts are in today's dollars; withdrawals and monthly investments keep pace with inflation. No taxes or fund fees. Past returns don't guarantee future ones. This is an estimate, not financial advice.