All Portfolios

Buffett 90/10

Growth Risk
Featured
MC fragile

Warren Buffett's passive benchmark: 90% low-cost S&P 500 index fund and 10% short-term government bonds. He recommended this in his 2013 shareholder letter as instructions for managing his wife's inheritance.

6
Diversification

Diversification

6

Volatility Profile

9.8%

5-year backtest

Horizon

10+ years

Virtual Demo Track Record

Forward performance on our internal virtual $1,000 demo account since 8/2/2026. This is not customer capital and not your brokerage account.

Compare all portfolios

Account value

$1,018.47

As of Sep 21, 2026 UTC

Total return

Cumulative since activation

+1.85%

Today's return

Since midnight UTC

0.00%

Tracking days

46

Total Return History

Cumulative return since activation — the same metric as the Total Return card above. A rising line means recovery over time; it does not mean today's return is positive.

Buffett 90/10

Hover a date for cumulative and that day's return. For today's move, see Today's Return in the summary.

Historical Performance

Simulated. 5.0-year daily MA200 → SHY trend filter at stated weights; next-open fills; paper one-way costs (15 bps) on entries/exits (2 holdings, as of 2026-09-18). Not a live track record — paper and house-account blotters are the forward book.

Monte Carlo block-bootstrap P5 Sharpe is below 1.0 on 5-year daily returns — demo track record only; paper and live trading are not available.

Annualized Return

+6.6%

5-year backtest

Volatility

9.8%

annualized

Net Sharpe

0.72

after paper fee + slippage

Max Drawdown

-20.0%

backtested

Sortino Ratio

1.08

return / downside vol

Gross Sharpe

0.78

before paper fee + slippage

VaR 95% (1-day)

-1.11%

historical, 5th-pctile day

CVaR 95% (1-day)

-1.51%

expected shortfall

Trading Logic

End-of-day signals only — no day trading. See full trading logic documentation.

Rebalance Schedule

Weekly (Mondays)

Drift > 5%

Min Holding

0 days

Before discretionary sells

Trend Filter

MA200 → SHY

Buy when MA stack aligned; exit to cash when broken

Risk Alerts

Defensive regime

VIX spike, DD halt — any business day

AI Rationale

Fixed 90% VOO / 10% SHY — faithful to the 2013 letter. A 200-day trend guard with 3-day entry confirmation steps equity to SHY when the S&P 500 loses structural support (Jul 2026 backtest: Sharpe ~1.18 vs ~0.78 buy-and-hold, max DD ~−9% vs ~−23%).

Bull Case

Ultra-low cost with trend overlay: backtest Sharpe ~1.18 vs ~0.78 buy-and-hold, max DD ~−9% vs ~−23%.

Bear Case

Monte Carlo block-bootstrap P5 Sharpe below 1.0. Trend exits can lag V-shaped recoveries.

Behavior During Downturns

When VOO falls below its 200-day average for three consecutive days, the equity sleeve rotates to SHY until trend recovers. The 10% bond sleeve remains as ballast.

Holdings

Fixed 90% VOO / 10% SHY (2013 letter benchmark) with MA200 + 3-day entry confirmation. Current allocation: VOO 90%, 10% SHY.

VOOVanguard S&P 500 ETF
90%
SHYiShares 1-3 Year Treasury ETF
10%
Research software — not a fund or adviser. We do not take custody. Live orders stay in your brokerage. Not financial advice. Past performance does not indicate future results.