Buffett 90/10 Portfolio Safe Withdrawal Rate Calculator

Historical performance and safe withdrawal rate analysis for the Buffett 90/10 Portfolio. See asset allocation, risk metrics, and success rates across different withdrawal strategies and retirement horizons.

Warren Buffett's recommended allocation for his wife's trust: 90% in S&P 500 index fund and 10% in short-term government bonds. Ultra-simple, ultra-low cost, high equity exposure.

Source: Berkshire Hathaway Annual Letter

CAGR (Annual Return)
8.4%
Maximum Drawdown
-46.5%

Worst year: -33.8%

Volatility
16.1%

Sharpe: 0.42

Best Year Return
33%

Asset Allocation

Historical Performance

MetricValue
CAGR (Annual Return)8.4%
Volatility (Std Dev)16.1%
Maximum Drawdown-46.5%
Sharpe Ratio0.42
Best Year33%
Worst Year-33.8%

Safe Withdrawal Rate Success Rates

Withdrawal Rate30-Year Success40-Year Success
Conservative (3%)100%92%
Moderate (3.5%)98%90%
Standard (4%)92%84%
Aggressive (5%)78%70%
100%30-yr success

Conservative (3%)

98%30-yr success

Moderate (3.5%)

92%30-yr success

Standard (4%)

78%30-yr success

Aggressive (5%)

Calculation Assumptions

  • Historical returns based on backtested data. Past performance does not guarantee future results.
  • Safe withdrawal rate success rates estimated from historical market data and Monte Carlo simulations.
  • Asset allocation weights are percentages of total portfolio.
  • CAGR, volatility, and drawdown figures are approximate based on historical averages for each asset class.
  • Actual results vary based on rebalancing frequency, fees, taxes, and withdrawal timing.

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