Buffett 90/10 Portfolio Backtest

Historical backtest of the Buffett 90/10 idea: 90% S&P 500 (SPY) and 10% short-term Treasury bills (BIL), rebalanced annually.

Backtest window: 2007-05-30 to 2026-06-05. Results as of 2026-06-05.

Assumptions

Results

Portfolio CAGR Max drawdown Volatility Sharpe Sortino Calmar
Buffett 90/10 (SPY/BIL) 9.8% -49.9% 17.5% 0.54 0.76 0.20

Growth of $10,000

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Historical simulation computed by the ArthaPilot backtest engine with total-return (dividends reinvested) prices and annual rebalancing, before taxes and fees. Past performance does not predict future results. This page is educational and is not investment, tax, or legal advice.