The 3.7% Withdrawal Rate: Why Experts Lowered It
The financial planning world experienced a quiet earthquake in recent years. The 4% rule, gospel for retirement planning since the 1990s, got downgraded. Morningstar, Vanguard, and other heavyweight research firms now suggest something closer to 3. 3-3 - 7% for new retirees.
This is more than academic hand-wringing. For someone with a $1 million portfolio, we’re talking about the difference between $40,000 and $37,000 in annual spending. Over 30 years, that gap compounds into hundreds of thousands of dollars in lifestyle adjustments.
The Original 4% Rule and What Changed
William Bengen introduced the 4% rule in 1994 after analyzing historical market data back to 1926. His method was straightforward: withdraw 4% of your portfolio in year one, then adjust that dollar amount for inflation each subsequent year. His research showed this strategy survived every 30-year period in history, including the brutal sequence of the Great Depression followed by World War II.
But three factors shifted since Bengen’s original work:
Bond yields collapsed. When Bengen ran his numbers, 10-year Treasuries yielded 6-8%. Today’s sub-4% environment means the “safe” portion of your portfolio generates far less income. A 60/40 portfolio once threw off meaningful dividends and interest. Now it requires selling more shares to meet that 4% target.
Stock valuations climbed. The Shiller CAPE ratio averaged around 15-16 historically. Recent readings have hovered near 30-35. Higher valuations typically predict lower future returns. Morningstar’s 2023 research projects 10-year annualized returns of just 4. 4% for a 60/40 portfolio, compared to historical averages near 8-9%.
Life expectancy increased - bengen designed for 30-year retirements. People retiring at 65 now routinely live into their 90s. A 35-year retirement horizon requires more conservative withdrawal rates to avoid outliving your money.
What the Numbers Actually Say
Morningstar’s 2023 study, led by Amy Arnott and Philip Straehl, ran Monte Carlo simulations on various withdrawal strategies. Their findings:
- 7% withdrawal rate: 90% success rate over 30 years
- 3% withdrawal rate: 90% success rate over 40 years
Vanguard’s research reached similar conclusions - their 2022 analysis suggested 3. 4% for portfolios with 50/50 stock/bond allocation, assuming current market conditions persist.
David Blanchett’s research at PGIM introduced another wrinkle: spending decreases as retirees age. His “retirement spending smile” shows expenses dropping in early-to-mid retirement (roughly ages 65-80), then potentially increasing for healthcare in very late retirement. This pattern means strict inflation adjustments might overstate actual spending needs.
Sequence of Returns Risk Gets More Dangerous
Here’s what keeps retirement researchers up at night: when you retire matters enormously.
Two investors could have identical portfolios earning identical average returns over 30 years. The one who retired just before a market crash might run out of money while the other dies with millions left over. This is sequence risk.
The math is brutal. If your portfolio drops 20% in year one and you withdraw 4%, you’re actually pulling out 5% of remaining assets. Do that again in year two after another decline, and you’ve created a hole you might never climb out of, even with strong subsequent returns.
Lower withdrawal rates provide cushion against this risk. Starting at 3. 7% instead of 4% means more portfolio preservation during those critical early years. Your portfolio has better odds of recovering from market downturns without being cannibalized by withdrawals.
Dynamic Strategies Beat Static Rules
The 4% rule assumes you mindlessly take the same inflation-adjusted amount regardless of market conditions. That’s absurd - no one actually does this.
Several dynamic strategies show better outcomes:
Guardrails approach: Establish spending bands. If your portfolio grows significantly, increase spending by 10%. If it drops below a threshold, cut spending by 10%. Jonathan Guyton’s research showed this method increased median portfolio values while maintaining spending flexibility.
Required Minimum Distribution (RMD) method: Calculate withdrawal as portfolio value divided by remaining life expectancy. This automatically adjusts spending based on portfolio performance. Downside: high volatility in annual income.
Percentage of portfolio: Withdraw a fixed percentage each year based on current portfolio value. Simpler than guardrails but provides similar downside protection.
Spending buckets: Maintain 2-3 years of expenses in cash/bonds, remainder in stocks. Refill cash bucket during strong market years, live off it during downturns. This lets you avoid selling stocks in bear markets.
What This Means for FIRE Seekers
Early retirement enthusiasts face even tougher math. Retiring at 40 means funding 50-60 years, not 30. Some FIRE calculators still show 4% as safe. They’re wrong.
For early retirees:
- 3 - 25-3.
Karsten Jeske’s “Early Retirement Now” blog analyzed this extensively. His Safe Withdrawal Rate series (40+ parts) showed that for 60-year retirements, safe withdrawal rates drop to 3. 25% or lower depending on asset allocation and risk tolerance.
The Flexibility Factor
Numbers only tell part of the story. Successful retirees treat spending as variable, not fixed.
Research by Blanchett and others shows actual retirees rarely increase spending with inflation every single year. They cut back during market downturns, spend more during windfalls, and generally adapt to circumstances.
This flexibility dramatically improves success rates. Being willing to reduce spending by 10-20% during severe bear markets can be the difference between portfolio survival and depletion. Most people discover they can cut discretionary spending (travel, dining, entertainment) without severely impacting happiness.
Social Security provides additional flexibility. Delaying benefits from 62 to 70 increases monthly payments by roughly 75%. Using portfolio withdrawals to bridge the gap, then dialing them back when Social Security kicks in, improves long-term sustainability.
Should You Actually Use 3. 7%?
Context matters - the 3.
- No pension or Social Security income
- 50/50 to 60/40 stock/bond allocation
- 30-year retirement horizon
- 90% success rate target (10% acceptable failure rate)
- Current market valuations and low bond yields persist
Your situation might justify higher or lower:
Higher withdrawal rates might work if:
- You have flexible spending and can cut back
- Social Security or pension covers basic expenses
- You’re willing to return to part-time work if needed
- You have home equity or other assets as backup
- You’re retiring later (70+) with shorter time horizon
Lower rates make sense if:
- You have inflexible expenses (medical conditions, dependents)
- Strong desire to leave inheritance
- Very early retirement (before 50)
- Conservative personality that values security over spending
The honest answer: 3. 7% isn’t gospel any more than 4% was. It’s a starting point for planning, not a straitjacket. Build flexibility into your retirement plan, monitor your portfolio, and adjust as needed.
Retirement planning remains part science, part art. The science says lower your initial withdrawal rate. The art is figuring out how to live well within those constraints.