Jane Austen described Mr. Darcy not as "worth 100,000 pounds" but as having "ten thousand a year." She was not being literary. She was being precise. In the 18th century, wealthy people measured themselves in income, not capital. Somewhere in the 20th century, we lost that instinct — and the entire retirement industry was built on the wrong unit of measurement. The FIRE community says "I need $1.2 million." Pension funds say "I need $48,000 a year, inflation-adjusted, for 30 years." These are not the same statement. The gap between them is the single largest source of error in individual retirement planning.
The Number That Feels Good
The FIRE community organises itself around a wealth target. It takes many forms:
- "My FIRE number is $1.2M"
- "I need 25× my annual spending"
- "At 4% withdrawal, $40,000/yr from $1,000,000"
These are wealth numbers. They measure the size of the pile. The pile is supposed to last 30 years, but the measurement does not contain the word "years." It does not contain the word "inflation." It does not contain the word "income." It is a snapshot of a balance — taken on one day, at one set of market prices and interest rates — that is supposed to fund a dynamic, multi-decade, inflation-sensitive spending stream.
JL Collins calls it "your number." Mr. Money Mustache calls it "the stash." The Bogleheads call it "the portfolio." All measure the same thing: how large is the pile. Not one of them — and I have read them all carefully — converts the pile to a sustainable real income at the no-arbitrage discount rate and reports the result in dollars-per-year. Collins's followers celebrate "hitting their number" at $1.2M. What they do not know is whether $1.2M buys $48,000/yr of real income (at a 2.3% TIPS yield) or $84,000/yr (at 7% — the rate they implicitly assume). The difference between those two numbers — $36,000 per year for the rest of their lives — is the gap between the wealth question and the income question. It is not a rounding error. It is the retirement.
The number feels good because it is large. A million dollars is a large number. It sounds like enough. But "enough" is a function of what the money needs to buy, and you cannot determine that by looking at the pile.
The Number That Funds a Life
Pension funds do not report their status as "we have $4.2 billion in assets." They report: "We are 87% funded — our assets can buy 87% of the income we've promised to pay."
The funded ratio is a ratio. Assets divided by the present value of the liability. The liability is not a pile — it is a stream. $X per year, adjusted for inflation, from retirement age through death. The present value of that stream changes every day as interest rates, inflation expectations, and mortality assumptions change.
When a pension consultant reports to the board, they show:
| Metric | Value |
|---|---|
| Assets | $4.2B |
| Liability PV | $4.8B |
| Funded ratio | 87.5% |
| Annual benefit payments | $380M |
| Duration of liability | 14.3 years |
The board does not celebrate or panic based on the asset number. They make decisions based on the ratio. Is it above 100%? We're fully funded. Below 100%? We need contributions, or a better hedge, or both.
This is precisely the measurement that individual retirement investors should be making — and none of them do.
Why the Conversion Matters: A Worked Example
Two investors, both age 55, both planning to retire at 65, both targeting $50,000/yr in real spending through age 90.
Investor A: January 2020
- Portfolio: $1,500,000
- FIRE community verdict: "Congrats! 30× spending. You're FatFIRE."
- 20-year TIPS yield: 0.5%
- PV of $50,000/yr real for 25 years at 0.5%: ~$1,220,000
- Funded ratio: $1,500,000 / $1,220,000 = 123%
- Income she can buy: ~$61,500/yr real
Investor B: January 2024
- Portfolio: $1,100,000
- FIRE community verdict: "Almost there. Need another $150k."
- 20-year TIPS yield: 2.2%
- PV of $50,000/yr real for 25 years at 2.2%: ~$970,000
- Funded ratio: $1,100,000 / $970,000 = 113%
- Income she can buy: ~$56,700/yr real
In wealth terms, Investor A is richer by $400,000. On Reddit, she gets 500 upvotes. Investor B gets encouragement to "keep saving."
In income terms, both are funded above 100%. Both can buy more than $50,000/yr in real retirement income. Investor A can buy $61,500/yr; Investor B can buy $56,700/yr. The difference is $4,800/yr — meaningful but not the gulf that the $400,000 wealth difference implies.
And here is the sharper point: Investor B's surplus is locked in if she buys a TIPS ladder today at 2.2% real. Investor A's surplus in 2020 was contingent on rates staying low — if rates rose (as they did), her liability shrank, but so did her portfolio. The funded-ratio frame reveals that the two investors are in much more similar positions than the wealth numbers suggest.
The wealth frame misleads. The income frame reveals.
What "Enough" Actually Means
"Enough" is not a dollar amount. It is a funded ratio.
- Funded ratio < 80%: Significant shortfall. The portfolio cannot buy the income stream. Either save more, spend less in retirement, work longer, or accept a lower standard of living.
- Funded ratio 80–100%: Approaching funded but still short. The gap can be closed by continued saving, favourable market moves, or modest spending adjustments.
- Funded ratio 100%: Fully funded. The portfolio can — right now, at today's rates — purchase the full consumption stream. This is the point at which the option to retire exists.
- Funded ratio 100–120%: Surplus. The portfolio exceeds the liability. The surplus is available for discretionary spending, legacy, risk-taking, or higher sustainable income.
- Funded ratio > 120%: Significant surplus. Consider: you are saving beyond what the liability requires. Is the additional savings serving a purpose — legacy, large one-off expenditure, buffer? Or is it over-accumulation driven by the wealth instinct rather than the income need?
Bill Perkins — Die With Zero — gets the objective function right: money has a time-value for experiences, and dying with a large pile means you over-saved and under-lived. This is a restatement of Merton's lifecycle consumption optimisation (1969). The optimal plan consumes the endowment. Terminal wealth is zero. But "spend it down" is a direction, not a navigation instrument — without the funded ratio, you cannot know when you've crossed 100% or how fast to go. A later post in this series — "Die With Zero Is Right — and It Needs Better Math" — gives Perkins the quantitative framework he's missing.
The FIRE community's "25× rule" (4% withdrawal rate) corresponds to a funded ratio of approximately 100% — but only at specific real interest rates. At 4% real yield, 25× gets you to roughly 100% funded. At 2% real yield, 25× gets you to approximately 130% funded (you're oversaving). At 0% real yield, 25× gets you to approximately 80% funded (you're undersaving).
The FIRE number is not wrong. It is incomplete. It gives one answer for all interest rate environments when the answer varies dramatically by rate. The funded ratio adjusts automatically: as rates change, the liability PV changes, and the ratio updates. You always know where you stand.
Why the Wealth Frame Persists (and Where It's Correct)
There is one category of investor for whom the wealth frame is not wrong: the ultra-wealthy.
Peter Mladina, in his Rational Reminder interview, draws the distinction precisely: "Ultra-high-net-worth investors tend to fully hedge consumption goals and hold surplus assets in the return-seeking portfolio." When consumption is fully funded — locked in with a bond portfolio that matches every year of spending — the remaining assets are surplus. Surplus is measured in wealth, not income, because there is no consumption liability left to fund. The surplus serves legacy, philanthropy, dynasty — objectives properly measured in capital, not in dollars-per-year.
The buy-borrow-die strategy follows directly. If consumption is hedged, the equity portfolio exists for wealth transfer. Never sell, borrow against it for discretionary spending, let the cost basis step up at death, and the capital gains tax is extinguished. This is a tax optimisation on surplus, not a consumption funding strategy. It is brilliant — and it has absolutely nothing to do with retirement planning for anyone in the FIRE community.
The FIRE community is not ultra-wealthy. It is — in Mladina's precise framing — "mass-affluent investors compelled to take risk to fund retirement." For these investors, the pile is not surplus. The pile is the only thing standing between them and a funded retirement. Measuring it in wealth units hides the question that matters: how much income can this pile buy?
The wealth instinct is not irrational. It is borrowed from the wrong class of investor. The ultra-rich measure in wealth because their consumption problem is solved. The FIRE community measures in wealth because the financial industry — built to serve the ultra-rich — never gave them a different tool. The funded ratio is that tool.
The Reporting Standard You Deserve
Every quarter, your brokerage sends you a statement that shows:
| Fund | Balance | Return (YTD) |
|---|---|---|
| US Stock Index | $520,000 | +8.2% |
| Int'l Stock Index | $180,000 | +4.1% |
| Bond Index | $100,000 | −1.3% |
| Total | $800,000 | +6.1% |
This tells you the size of the pile and how much it grew. It does not tell you the one thing you need to know: can this portfolio fund my retirement?
The statement you should receive:
| Metric | Value |
|---|---|
| Portfolio | $800,000 |
| Consumption liability PV | $930,000 |
| Funded ratio | 86% |
| Sustainable real income | $43,200/yr |
| Target income | $50,000/yr |
| Gap | −$6,800/yr |
| Duration gap | −12.3 years |
| Inflation exposure (βπ) | −0.52 (unhedged) |
| Rate exposure (βᵣ) | −0.78 (unhedged) |
Nine numbers. Everything you need to make every retirement investment decision. How much to save, what to buy, when to retire, and what you can afford.
No retirement platform shows this. Not Fidelity, not Vanguard, not Schwab, not any of the FIRE calculators. They show the pile. The pile is the wrong number.
Mr. Darcy Understood This
Austen's world did not have index funds, retirement accounts, or TIPS. But it had something the modern retirement industry lacks: the correct unit of measurement.
When Austen described Darcy as having "ten thousand a year," every reader understood immediately what that meant. He could afford a country estate, a London townhouse, servants, horses, travel, and the education of his children. The income — not the capital that generated it — was the measure of his position. The capital was invisible. The income was the life.
When Austen described Mr. Bennet — whose estate was "entailed away from the female line" — the crisis was not that the family would lose wealth. It was that the family would lose income. Mrs. Bennet's famous anxiety was not about a smaller pile. It was about £2,000 a year becoming £500 a year. The unit was always income. The risk was always income.
We lost this instinct when retirement became an individual responsibility rather than a family or institutional one. Pension funds kept the instinct — they report in income units because they must pay income. Individuals dropped it, because the retirement industry sells products measured in balance growth (which earns the industry fees) rather than income capacity (which would reveal that most investors are underfunded).
The funded ratio restores the measurement. It converts the pile back to income. It answers, every day, in real terms, the Austen question: "What is your ten thousand a year?"
The Conversion Formula
To convert your net worth to your funded ratio:
Where:
- = planned real spending in year
- = real discount rate (TIPS yield of matching maturity)
- = probability of surviving to year (from mortality tables)
- = planning horizon (e.g., age 95)
The numerator is the pile. The denominator is the real cost of the income stream. The ratio tells you what fraction of your retirement you can buy — today, at today's rates.
When the ratio is above 1.0, you have a surplus. When it is below, you have a deficit. The deficit, expressed in income units, tells you exactly how far from retirement you are — not in dollars, but in dollars-per-year-of-living. That is the number that matters.
Retirement is not a pile of money. It is a stream of income. Mr. Darcy knew this. Pension funds know this. The FIRE community — for all its analytical sophistication — measures the wrong thing. Convert from wealth to income. Calculate the funded ratio. Know your number — not in dollars saved, but in dollars per year you can spend, adjusted for inflation, for the rest of your life.
Next week — the capstone post: "The One Number That Matters." The full framework in one post. How to calculate your funded ratio from scratch, step by step. And a tool that does it for you. Subscribe to get it on launch day.
This is Post 9 of The Funded Ratio — a series on amifunded.com applying pension fund mathematics to individual retirement portfolios. Built on the Campbell-Viceira (2002) intertemporal asset allocation framework, the lifecycle consumption theory (Merton, 1969; 1971), and the liability-driven investing practices used by pension funds, endowments, and sovereign wealth funds worldwide. "Ten thousand a year" — Jane Austen, Pride and Prejudice (1813). No financial advice is given. All methods use publicly available academic research and market data.