4% Rule vs the Real 2016 to 2024 Market Path

The first big FIRE wave quit work in the mid-2010s with one instruction taped to the portfolio: the 4% rule. Take $40,000 from a $1,000,000 portfolio the first year, adjust that number for inflation every year after, and stop thinking about it. That cohort has now lived the decade everyone warned about, and ten-year retrospectives are rolling in, including this ten-year FIRE retrospective on how early retirement actually feels. What the anniversary coverage mostly skips is the arithmetic. This piece is the arithmetic.

The 4% rule survived 2016 to 2024, and it was not close, but the reason it survived should make anyone retiring around 2026 nervous rather than comfortable. A violent bull market ran for roughly five years before the first real stress arrived, which makes this decade a demonstration of sequence luck more than rule robustness. The 2020 COVID crash, terrifying on a daily chart, recovered too fast to threaten a 40-year plan. The genuine stress test was 2022, when stocks, high-quality bonds, and the purchasing power of the withdrawal dollars all broke in the same year. That joint shock, landing in years five to ten rather than year one, is the scenario to engineer against.

Everything below is reproducible: the full model first, the raw market path, the year-by-year ledger, the counterfactuals that keep the luck honest, and the rules worth keeping.

The first FIRE wave just closed decade one

The 2016 cohort has one claim to fame nobody else gets: they retired into a market that cooperated immediately. Everyone who left work between 2016 and 2020 with a 4% plan was, without knowing it, running a live experiment in sequence of returns risk. That experiment is now old enough to grade, and the lived, ten-year results of a 2016 FIRE retiree are worth more than any 2015 backtest, because nobody got to choose the returns in advance.

Generic coverage splits into two camps: abstract sequence risk explainers with no numbers, and celebration from retirees who are still solvent. Neither tells you which year did the damage, why the bond cushion failed, or which decision rules would have fired. This case study does, from four stated inputs:

The model. $1,000,000 invested January 1, 2016: 60% US stocks (S&P 500 total return) and 40% US aggregate bonds. The first withdrawal, $40,000, comes out January 1, 2016. Every later January's withdrawal equals the prior year's times the December-to-December change in CPI. The mix rebalances to 60/40 annually. No taxes, no fees, calendar-year arithmetic throughout. Figures are rounded, so your rerun may differ by rounding error, not by conclusion.

One cutoff: the ledger closes at end-2024, the last year for which all the index and CPI prints used here are settled and published. Extend it to 2026 with the same two sources. To calibrate how much the missing years could matter, stack 2022's portfolio return twice onto the end of this ledger and the balance still finishes above its starting $1,000,000.

The exact market path a 2016 retiree lived

Before any interpretation, the raw path. Stock returns are S&P 500 annual returns, bond returns are the US Aggregate Bond index, and inflation is December-to-December CPI from the Bureau of Labor Statistics. Rounded to one decimal.

Three things jump out. First, seven of nine stock years were strongly positive, and the only down year before 2022 cost less than five percent. Second, the scariest event of the decade does not appear in the table at all: the 2020 crash lives inside a +18.4% calendar year. Annual data hides intraday terror, which is exactly why a retiree needs to distinguish a crash that threatens the plan from one that only threatens sleep. Third, the bond sleeve posted two losing years in 2021 and 2022, the first back-to-back down years in the modern aggregate index's history, and the big loss arrived the same year stocks fell.

Running the 4% rule portfolio year by year

Apply the model to that path and the decade looks like this. The current withdrawal rate is each January's withdrawal divided by the portfolio value that morning, the number a guardrails strategy actually watches.

Read the bottom row first. Nine withdrawals totaling about $402,000 left the portfolio at roughly $1.61M at end-2024, up 61% in nominal terms and about $1.2M in 2016 dollars, a 20% real gain. The current withdrawal rate touched its starting level once more (2019) and never exceeded it, then entered 2025 near 3.3%.

Conventions matter at the margin: shift withdrawals to year-end or use average CPI instead of December prints and the ending figure moves within roughly $1.5M to $1.7M. No reasonable convention changes the direction of the result, which is the point of stating the model in full.

2020 was the scare, 2022 was the stress test

For early retirement, the COVID crash was a sequence risk scare, not a sequence risk event. US stocks fell about 34% from February 19 to March 23, 2020, one of the fastest bear markets on record, then recovered the whole loss by late August, inside a calendar year that finished +18.4%. On the worst daily marks the model briefly dipped to roughly $1.1M, still above its starting line, because the 40% bond sleeve rallied modestly while stocks collapsed and held the whole-portfolio drawdown to the high teens. It finished 2020 ten percent above where January began. The withdrawal had already been paid in January, so nothing was sold at the bottom under this convention. A crash that round-trips within months tests temperament more than it tests a 40-year plan.

2022 was the opposite in every dimension. Stocks lost 18.1%. The aggregate bond index, whose entire job was cushioning that, lost 13.0%. The December 2022 CPI release put inflation at 6.5% for the year on top of 7.0% in 2021, which forced the withdrawal up to $47,160 from $44,080, paid the same January the portfolio was falling. The 60/40 portfolio's 2022 drawdown, about a sixth of its value in one calendar year, is the kind of number that pushed Morningstar's 60/40 analysis to ask whether the mix still works.

In dollars: the model ended 2021 at $1,567,000 and 2022 at $1,276,000. That $291,000 hole, roughly $244,000 of market loss plus the withdrawal, was the decade's only serious damage, and it landed in year seven, after five good years had thickened the cushion. So did the 4% rule survive 2022? Comfortably, and mostly because 2016 through 2021 had pre-paid the bill. A retiree who started in 2022 got no such cushion.

The inflation tax nobody had modeled

Cumulative inflation from 2016 to 2024 came to roughly a third; the BLS inflation calculator puts $1.00 of 2016 purchasing power at about $1.33 by late 2024. That single number did two separate things to FIRE plans.

Anyone running classic inflation-adjusted withdrawals watched the paycheck climb relentlessly: $40,000 in 2016, $47,160 by 2022, $51,940 in 2024, about $53,400 scheduled for 2025. The mechanism that protects purchasing power is the same mechanism that amplifies bad sequences, because it raises withdrawals in the exact years the portfolio is falling. 2022 delivered both at once, a 7% raise paid into a 16% decline.

Anyone who quietly skipped the adjustment and spent a fixed $40,000 paid a silent tax instead. That $40,000 in 2024 bought what about $29,900 bought in 2016. A quarter of the retirement, reclaimed by prices, with no statement line ever showing it. Running out of money is the failure everyone models. Keeping the money while the life it funds shrinks by a quarter is the failure nobody does.

Why the 4% rule survived anyway, and when it would not have

The mechanism is embarrassingly simple: the returns arrived early. US stocks compounded at roughly 17% a year across 2016 through 2021, and the 60/40 roughly doubled before 2022 appeared. Withdrawals came out of gains, the balance peaked at $1.567M, and the plan entered its worst year carrying a 3.0% current withdrawal rate. A portfolio that sells 3% a year absorbs a 16% hit and keeps breathing; the same hit on a fresh 4% portfolio is a different animal.

The safe withdrawal rate literature has said this all along. William Bengen's 1994 paper and the Trinity study that followed defined 4% as the rate that survived the worst starting cohorts on record, 1929 and the inflation-shredded late 1960s and 1973, and Trinity study retrospectives still frame it that way. Surviving a friendly draw proves nothing about that floor. This decade tested the rule the way a crash test proves a car that never hit the wall.

Two counterfactuals keep the luck honest.

Shift the start to January 2000. Stocks fell 9.1%, 11.9%, and 22.1% in the first three years. A 4% inflation-adjusted plan spent the better part of the following decade underwater in real terms, the canonical bad-sequence outcome, under a rule carrying the exact same label.

Shift the start to January 2022. Same rule, same markets, a six-year difference. The identical model on the identical returns produces a second ledger:

The year-two rate clears the 4.8% line where guardrail strategies order a spending cut, so this cohort takes an automatic pay cut in 2023, while the 2016 cohort, on the same markets, enters 2025 at 3.3% and never comes near a cut. Three years in, the 2022 retiree is still underwater, carrying a 4.6% rate into 2025 with no cushion behind it. The rule was constant. The sequence was not.

Withdrawal rules the decade hands the 2026 cohort

The lesson is to keep the 4% rule and stop treating a static number as the plan. Four rules follow, each one read off a ledger line above.

1. Check the current withdrawal rate every January. Both ledgers start at 4.0%; by 2025 the 2016 one runs at 3.3% while the 2022 one took a 5.3% year-two rate and a forced cut. Identical markets, identical rule, and the only number that separated the two outcomes was the current rate, recalculated each January as coming spending divided by that morning's balance. Guardrails in the Guyton and Klinger style act on exactly that number, cutting spending about 10% when the rate rises 20% above its starting level (above 4.8% on a 4% plan) and raising it below 3.2%. Across this ledger that rule fires zero cuts for the 2016 retiree and exactly one, in year two, for the 2022 one.

2. Pair spending bands with a cash sleeve. The bands: a hard floor at 85% of initial real spending, so bad markets produce small lifestyle adjustments instead of solvency questions. The sleeve: one to two years of spending in cash. Both answer the same ledger line. In January 2022 the model sold bonds that went on to lose 13% for the year, to fund a 7% raise, the most expensive withdrawal of the decade. The cash sleeve would have paid that bill and let those bonds capture 2023's 5.5% recovery, and the bands would have given the forced cut a defined bottom. This decade never tested the floor. The cash was needed anyway.

3. Rebuild the bond tent around inflation, not duration. The decade's verdict on Kitces's bond tent is split: the construct survived 2022, its material did not. Long nominal Treasuries lost roughly 30% that year, moving with equities exactly when the tent was supposed to hold, while short TIPS, I bonds, and cash kept their ground. Keep the tent. Change what it is made of.

4. Stress-test years five through ten. Every calculator runs a 1929 or 1973-style year-one disaster. This decade's template is the joint shock, stocks down 18%, bonds down 13%, CPI up 6.5%, landing mid-decade after the plan has stopped feeling fragile. That is the one test no 1929-style calculator runs. Run it yourself across years five, six, and seven of your own projection and watch what the withdrawal rate does.

A stress test checklist for your own plan

One evening, your own numbers:

1. Rebuild the ledger. Two index return series and one CPI series are the entire dataset. Paste in your balance and spending and extend the table to today.
2. Compute your current withdrawal rate every January. Write the tripwires down in advance: cut 10% above roughly 4.8% for a 4% start, resume raises below roughly 3.2%.
3. Check the real balance, not the nominal one. Divide by cumulative inflation since your start date; nominal highs can hide real losses.
4. Count the cash runway. One to two years of spending held outside the portfolio.
5. Audit the bond sleeve for a 2022 repeat. Ask what fraction would lose double digits if stocks fell 18% while CPI ran 6.5%, and justify any answer above zero.
6. Schedule the mid-decade stress. Insert the 2022 triple into years five through seven of your projection and confirm the guardrails fire before the portfolio does.

The 2016 cohort's decade says less about the 4% rule than about who was holding it. The order of returns dominated the outcome, the order was friendlier than anyone deserved, and the rules that mattered were written before the bad year arrived. Write yours down before yours does.