Chapter 13: Your one-page plan

Over the ten years to 2024, the average fund investor earned 7.0% a year in funds that returned 8.2% (Morningstar, Mind the Gap 2025). The missing 1.2 points were not fees, and they were not bad funds. They were decisions, entries and exits made at felt moments, concentrated in the most volatile funds where feelings run hottest. Twelve chapters of this guide chose your goals, your mix, your funds, and your rules. This last chapter is about the single page that protects all of it from the only investor who can reach it: you, on a bad day.

Institutions solved this problem decades ago. Pension funds and endowments write an investment policy statement, a standing document that records the allocation, the rules, and the permitted exceptions, so that no committee member can panic with the fund's money no matter how loud the quarter gets. The committee can meet, fume, and vote, and the document still says what it said. Yours works the same way with a cast of one. Future-you will someday read a headline, feel a drop in the stomach, and reach for the account password. The page is what stands in the way, holding eleven lines you wrote in order, each one on a calm day, each one with the evidence attached.

What is an investment policy statement?

A short written contract between you and future-you. It names who the money is for and when it is needed, states the target mix and the bands around it, lists every holding with a one-line reason, records the contribution autopilot and the rebalancing trigger, and ends with the things you have promised not to do. Institutions write them so committees cannot improvise; you write one so a Tuesday cannot. The power is not legal, since nobody will sue you for breaking it. The power is that a specific sentence, written by you in a calm hour with the reasoning attached, is much harder to override than a vague intention. Chapter 9 found your worst-year dollar line; the page is where that line lives, next to the rule that any change must wait 30 days. One page is the right length on purpose: short enough to reread in two minutes, short enough that every line earns its place, and short enough that there is nowhere for a bad idea to hide.

The template

Eleven plan lines accumulated across this guide. Here they are assembled, with the two closing sections, the refusals and the change rule, that turn a list into a policy.

The annual hour, walked once

The plan runs on one scheduled hour a year, four blocks of fifteen minutes. Mara books hers for the first Saturday of March, next to the tax folder; the month matters less than the calendar entry.

Minutes 0–15, the page read. Read the whole plan aloud, then test the first line against reality, confirming the goals are still the goals and the dates are still the dates. A new job, a new child, a house plan moving closer, an inheritance landing, any of these re-runs Chapter 1 for the affected dollars only. Money whose date has moved inside about five years leaves the mix for the safe shelf. Most years, nothing has changed, and this block ends in four minutes.

Minutes 15–30, the drift check. Pull current balances, compute the actual weights, and set them against the targets and bands. Inside the bands, do nothing; rebalancing more often than the rule demands buys no measurable risk control (Vanguard's research lineage, 2015 through 2024). Outside a band, fix it in the order the plan states: new money first in taxable, sheltered sales second. Mara's 70/30 drifted to 73/27 last year, inside her band, so block two was a look and a nod.

Minutes 30–45, the cost and creep check. Reread every holding's one-line reason and its fee. Index ingredients should still cost about 0.03–0.05%; anything pricier must re-earn its line this year, in writing. Check the explore sleeve against its cap, because winning sleeves grow past 2% by themselves and the cap is the promise. Confirm the autopilot amount rose with the last raise. This is also where any pitch collected during the year gets its hearing: fee said out loud, 2022-style receipt requested, line on the page identified, and usually, declined.

Minutes 45–60, the change page. Read the "I will not" list slowly. Then review any urges written down during the year: each one is now at least a few weeks old, which is the 30-day rule doing its work, and most will look like weather rather than information. Whatever survives a re-read of Chapter 9 can be edited into the plan today, dated and initialed. Book next year's hour, close the folder, and take the permission seriously: the plan does not want your attention until then.

The aisle, one verdict per stall

Chapters 7 and 8 walked the industry's whole menu. One line each, with the receipt attached.

The glossary

Twenty-six terms cover this guide's working vocabulary, each with the chapter where it earned its full explanation.

• Asset allocation: the split of a portfolio across stocks, bonds, and cash; the decision that sets the size of your worst year (ch. 2).
• Band: the drift allowance around a target weight, commonly 5 points, that triggers a rebalance when crossed (ch. 10).
• Behavior gap: the distance between what funds return and what their investors earn; 7.0% versus 8.2% over the ten years to 2024 (ch. 6).
• Bond tent: a glide path where the bond share peaks at the retirement date and equities drift back up afterward (ch. 11).
• Bucket: a pool of money assigned to one goal and date, run at its own risk level (ch. 1).
• Capital market assumptions: a firm's published forward return ranges; model assumptions, never promises (ch. 2).
• Collective investment trust (CIT): a fund structure common in 401(k)s, now holding 54% of target-date assets (ch. 7).
• Correlation: how much two assets move together; the stock-bond version turned positive in 2022's inflation shock (ch. 3).
• Direct indexing: owning an index's stocks individually in an SMA for tax harvesting and customization, at 0.10–0.40% (ch. 8).
• Drift: the slow rewrite of your mix by markets; how a 60/40 becomes a 68/32 without a decision (ch. 10).
• Expense ratio: a fund's annual fee as a share of assets; the index convention runs 0.03–0.05% (ch. 7).
• Explore sleeve: a small, named, capped allowance for speculation, kept so it cannot quietly become the portfolio (ch. 8).
• Glide path: a pre-written schedule shifting the mix as a date approaches (ch. 11).
• Guardrails: withdrawal rules that adjust spending after good and bad years instead of holding a fixed rate (ch. 11).
• Home bias: holding more of your own country's market than its world weight; the US is 63.5% of the world index, most American portfolios hold more (ch. 4).
• Investment policy statement: the written plan this chapter assembles; the institution's anti-panic document, sized for one person (ch. 13).
• Rebalancing: returning drifted weights to target by rule; risk control, not return enhancement (ch. 10).
• Risk capacity: what your life can absorb, set by horizon, income, and obligations (ch. 9).
• Risk need: the return your goal requires, tested against published return assumptions (ch. 9).
• Risk parity: balancing by risk contribution rather than dollars, usually with leveraged bonds; weather-dependent, as 2022 showed (ch. 8).
• Risk tolerance: what your sleep can absorb, measured honestly in dollars, not percentages (ch. 9).
• Sequence risk: the danger of bad years arriving early in retirement; order matters once withdrawals start (ch. 11).
• Target-date fund: a fund that runs a whole glide path under one ticker, the 401(k) default (ch. 7).
• Three-fund portfolio: total US market, total international, total bond; the Bogleheads convention, silent on splits by design (ch. 7).
• Withdrawal rate: the share of a portfolio drawn in year one of retirement; the research brackets 3.9–4.7% (ch. 11).
• Worst-year line: history's worst annual loss at your mix, written in dollars and read out loud before you commit (ch. 2, 9).

How current are these numbers?

Treat the table below as already aging, because research moves. Morningstar re-runs its withdrawal study every December and the safe rate has moved year to year; Vanguard's return assumptions are re-run quarterly and BlackRock's disagree with them by design; the DOL's 401(k) alternatives rule was still a proposal when this guide went to press, with the final version pending; fees keep drifting down and asset totals keep drifting up. The slow half of the table, the history, the study findings, the worst-year records, changes rarely. The fast half, anything dated 2025 or 2026, should be replaced with the current edition from the same source before you lean on it. That trace-everything habit is also the standard to hold every future pitch to: a named source, a stated period, and a number that survives being checked.

Every number, dated and sourced

The meta-lesson

Step back far enough and thirteen chapters compress into one idea with two halves. The allocation decides the size of your bad years: that is Chapter 2's table doing the work it has done since 1926, and every mix in this guide was read off it rather than guessed. Your behavior decides whether you actually receive the returns your allocation earns: that is the 1.2-point gap, the rebalancing band, the refusals list, and the 30-day rule, all of them guarding the same door. Products will keep arriving, rules will keep changing, and the table above will age a little every quarter. The method does not: every dollar a job and a date, every mix a worst year you accepted in writing, every holding one honest line, and all of it on a page that future-you can read in two minutes, on the exact day reading it matters.

Key takeaways

• An investment policy statement is the institution's anti-panic tool sized for one person: eleven plan lines, a refusals list, and a 30-day change rule on one signed page.
• The page exists because of the behavior gap: investors earned 7.0% in funds returning 8.2% over the ten years to 2024, and the difference was decisions made at felt moments.
• Maintenance is one hour a year in four blocks: read the page, check the drift against the bands, re-earn every fee, then review urges that have survived 30 days.
• The aisle verdicts compress two chapters: cheap recipes win by default, expensive ones must buy behavior, and every stall owes you a fee said out loud and a 2022 receipt.
• Every number in this guide carries a source and a period, and the fast half of the table goes stale by design; replace it from the same sources before leaning on it.

Sources: Vanguard model-allocation data · Vanguard return forecasts (VCMM) · Vanguard on international allocations · Vanguard rebalancing research (December 2024) · CFA Institute on the Brinson record · AQR on the stock-bond correlation · AQR on value investing · Bogleheads three-fund convention · Morningstar target-date fund research · Morningstar State of Retirement Income · Morningstar 60/40 stress test · Morningstar bucket approach · Morningstar Mind the Gap · SPIVA U.S. scorecard · Pfau & Kitces, rising equity glide paths · Kitces on the bond tent · Schwab on sequence-of-returns risk · BlackRock on sizing bitcoin · White House EO 14330 · DOL proposed safe-harbor rule · MSCI ACWI factsheet · Finvest Stocks Guide · Finvest ETFs & Funds Guide · Finvest Cash & Bonds Guide · Finvest Personal Finance Guide · Finvest Tax Playbook · Morgan Stanley, Cerulli, Swensen's Unconventional Success, BlackRock's capital market assumptions, and Bengen's A Richer Retirement (2025), named without links