My strategy is and has been the same for the last 10+ years Don't spend, but save up everything, invest it, and try live off the 4% returns 4% is the "safe withdrawal rate", this is the percentage of your investment portfolio you can withdraw each year without running out of money over a given time horizon, as in your balance stays the same even after inflation I have many friends who spend most of their money on expensive purchases of things tha depreciate in value (and I too have a Tesla Y that does that 😂) but if you do that you'll never get to any state of FIRE (retire early) where you can live off of your investments Many people in FIRE have relatively humble goals: $600K means $2,000/mo from your investments to live off forever, multiply that and $6M means $20,000/mo forever There's obviously caveats: do investments like ETFs keep returning forever or not, nobody knows. Diversifying your investments into other things like commodities (gold), real estate, and some angel investing also can work! The point is to spend less, invest more and then spend from what you take out of your investments
Diagram showing the spectrum of retirement spending strategies — including the dollar-plus-inflation approach (the 4% rule), dynamic spending, and percentage-of-portfolio — and how each trades off sensitivity to market performance, spending stability, and portfolio viability. It directly illustrates the tweet’s point about the 4% ‘safe withdrawal’ approach and alternatives (e.g., being flexible or using dynamic rules) for sustaining withdrawals from investments.
Source: Vanguard (advisors.vanguard.com)
Research Brief
What our analysis found
The viral tweet promoting a "save everything, invest it, and live off 4% returns" strategy taps into the widely known 4% rule, a retirement planning heuristic that originated with financial planner William P. Bengen's 1994 empirical research. Bengen backtested rolling 30-year periods of U.S. stock and bond returns dating to 1926 and found that an initial withdrawal of 4% of a portfolio, adjusted upward each year for inflation, historically survived every tested window. The concept was further validated by the Trinity Study (Cooley, Hubbard & Walz, 1998), which ran similar historical simulations and cemented the figure as a cornerstone of both mainstream financial planning and the Financial Independence, Retire Early (FIRE) movement.
The tweet's math aligns with the commonly cited rule of 25: because 1 ÷ 0.04 = 25, a retiree needs roughly 25 times their annual spending saved. Under that framework, a $600,000 portfolio supports about $2,000 per month, and $6 million supports about $20,000 per month. These figures check out as arithmetic applications of the heuristic and are consistent with how T. Rowe Price and other major planning firms present FIRE targets.
However, the tweet's characterization of 4% as the rate at which "your balance stays the same even after inflation" is a significant oversimplification. The original research models a declining but non-zero balance over 30 years, not a perpetually stable one. Moreover, contemporary forward-looking analyses paint a less optimistic picture. Morningstar's 2024 State of Retirement Income report, using current return forecasts, pegs the 30-year safe starting withdrawal rate at approximately 3.7% for balanced portfolios. For early retirees facing 40- to 60-year horizons, independent research from EarlyRetirementNow suggests safe fixed withdrawal rates may drop to around 3.4% or lower, making the traditional 4% figure potentially risky for the very FIRE adherents the tweet addresses.
Fact Check
Evidence from both sides
Supporting Evidence
Bengen's 1994 historical backtests validate the 4% starting point
William Bengen tested rolling 30-year U.S. return sequences from 1926 onward and found a 4% initial, inflation-adjusted withdrawal survived every historical period, establishing the empirical foundation the tweet relies on (Financial Planning Association, 1994).
The Trinity Study independently confirmed the finding
Cooley, Hubbard, and Walz (
ran similar historical simulations across various stock-bond mixes and reported ...
ran similar historical simulations across various stock-bond mixes and reported high survival rates for a 4% initial withdrawal over 30 years, helping popularize the rule (RetirementResearcher.com).
The rule-of-25 math in the tweet is accurate
Because 1 ÷ 0.04 = 25, a portfolio of roughly 25 times annual spending is the standard FIRE savings target. The tweet's examples of $600K supporting $2,000 per month and $6M supporting $20,000 per month are correct applications of this widely used heuristic (Kiplinger).
Major financial institutions still use 4% as a baseline planning figure
T. Rowe Price and other mainstream advisory firms continue to cite the 4% rule and the rule of 25 as a reasonable starting framework for retirement and FIRE planning (T. Rowe Price).
Dynamic strategies can make 4% or higher withdrawals feasible
Research on guardrail methods such as the Guyton-Klinger approach shows that retirees willing to adjust spending in response to market conditions can sustain initial withdrawal rates at or above 4%, adding flexibility the rigid rule does not capture (Morningstar).
Contradicting Evidence
The tweet mischaracterizes how the 4% rule works
The tweet states that at a 4% withdrawal rate "your balance stays the same even after inflation." In Bengen's original model, the portfolio balance is expected to decline over time; the rule is designed so the balance does not hit zero within 30 years, not that it remains constant (Financial Planning Association, 1994).
Low current yields undermine the historical 4% success rate
Finke, Pfau, and Blanchett (
recalibrated withdrawal models using low bond yields and elevated equity valuati...
recalibrated withdrawal models using low bond yields and elevated equity valuations and found significantly higher failure probabilities for a fixed 4% real withdrawal, concluding the rule may not be safe under contemporary market conditions (Financial Planning Association, 2013).
Forward-looking estimates put the safe rate below 4%
Morningstar's 2024 State of Retirement Income report, using current capital-market assumptions, calculates a 30-year safe starting withdrawal rate of approximately 3.7% for balanced portfolios, explicitly noting that historical backtests overstate what future retirees can safely withdraw (Morningstar, 2024).
FIRE's longer time horizons further reduce the safe withdrawal rate
Early retirees may need their portfolios to last 40 to 60 years, not just 30. Detailed analysis by EarlyRetirementNow shows that extending the horizon to 40 years drops the worst-case safe fixed withdrawal rate to roughly 3.43%, making the 4% rule materially riskier for the FIRE audience the tweet targets (EarlyRetirementNow).
Taxes, fees, healthcare shocks, and sequence-of-returns risk are ignored
The tweet omits several real-world factors that erode portfolio longevity, including investment fees, tax drag on withdrawals, unexpected healthcare costs, and the outsized impact of poor early returns known as sequence-of-returns risk, all of which can cause a nominally safe 4% plan to fail in practice.
Report an Issue
Found something wrong with this article? Let us know and we'll look into it.