Bengen Updates 4% Rule Baseline to 4.7% for Diversified Portfolios Entering 2026

Bengen's original Journal of Financial Planning paper tested rolling 30-year periods and identified 4% as the rate that survived the 1966-1995 sequence with zero terminal value. Subsequent updates incorporating small-cap and international equities raised the ceiling because those series reduced the maximum drawdown impact in the first decade. Morningstar's 2023-2025 annual reports have tracked safe rates between 3.8% and 4.2% depending on equity valuations at retirement, confirming no fixed percentage holds across regimes. Sequence-of-returns risk remains the binding constraint. Retirees facing negative real returns in years one through three deplete principal at depressed prices, an outcome Bengen quantified as requiring an initial 20-25% buffer versus average-return scenarios. Data from the 2000 and 2008 cohorts show fixed 4% withdrawals left portfolios 15-30% smaller after decade one than variable rules that cut spending after market declines. Variable strategies that adjust for trailing twelve-month inflation and portfolio value have produced median terminal wealth 40% higher than rigid rules in both Bengen and Blanchett simulations. For 2026 retirees, forward P/E ratios above 22 and real yields near 2% tilt the distribution toward the upper end of the historical range.