Bill Bengen Finds 9.6% Safe Withdrawal Rate With Guyton-Klinger Rules

1 articles · Updated · The Daily Upside · Aug 6

Bengen’s latest analysis puts the Guyton-Klinger strategy’s average maximum safe starting withdrawal rate at 9.6%, far above the traditional inflation-adjusted approach tied to his well-known 4% rule.
The method starts retirees at a higher income level, then adjusts withdrawals up, down or not at all each year based on portfolio performance and the current withdrawal rate.
Across 361 retirement scenarios, Bengen found a trade-off: conventional inflation-adjusted withdrawals produced higher cumulative real income in all but one case, often by a wide margin.
He said the gap can reach 60% to 70% in extreme scenarios, making the approach better suited to retirees who value higher income early and accept later cutbacks.
The findings extend Bengen’s long-running rethink of the 4% rule—raised to 4.5% in 2006 and 4.7% in 2021—as he prepares to test Warren Buffett’s 90/10 retirement-income idea next.