Retirement Abaques · Index

Design charts for US retirement law

Twelve nomograms in the résistance des matériaux tradition — enter with a load, follow a curve, read off an allowable. Each is drawn from legislation rather than from anyone’s finances, over a single canonical register of 97 statutory thresholds, each carrying its citation, its base year, its sunset, its confidence flag and its drift law.

Arithmetic, not advice. Every sheet shows its own working. Nothing here is personalised investment or tax guidance.

Twenty-six of the ninety-seven figures are re-set every January. Get notified when they are re-verified →

Entries97
Verified94
RevisionD
Snapshot2026
Sheets12
RegisterCC BY 4.0
The finding

Why sheet 01 has a wall in it

Measure a retirement plan in years of salary rather than dollars and the pay cancels out of balance, contribution and target alike. One curve then serves every reader, whatever they earn. That is what makes a chart an abaque rather than a case study.

Salary re-enters in exactly one place, and it is worth knowing why:

Congress wrote the §402(g) deferral limit as a dollar amount rather than a percentage of compensation. That single drafting choice is the entire reason the chart has a wall in it — and the wall moves closer the more you earn.

A purely legislative effect on a financial trajectory, isolated and drawn. Sheet 01 is where to start.

The sheets

Twelve, self-contained, no external requests

#SheetWhat it shows
00The Statutory RegisterThe datum sheet every other sheet depends on
01What the Shelter Can CarryLoad against allowable, in years of salary
02Roth vs Pre-taxt_now mapped against t_ret
03The True Marginal Rate CurveStatutory rate vs. what you actually pay
04The Legislated Age TimelineEvery age Congress wrote down
05The Retirement CorridorSynthesis
06The Shelter CeilingWhere the plan stops accepting money
07The ACA Premium Credit CliffA genuine discontinuity, not a ramp
08The 0% Capital Gains WindowThe window, and what closes it
09Early AccessThe routes out before 59½
10The Phase-out AtlasEvery phase-out on one plane
11The Cheat SheetEvery figure computed from the register at load

Bracket edges are ramps, not cliffs. The real cliffs — IRMAA, the Social Security torpedo, the ACA subsidy edge — get sheets of their own.

January

Every indexed figure goes stale

Twenty-six of the ninety-seven entries are re-set each January by the IRS, SSA, CMS or HHS. A snapshot is a snapshot of a moment, which is why this one carries its compile date. When the next set of figures is published and re-verified against primary sources, the register is revised and the changelog records which values moved.

If you maintain these numbers yourself, that notice is probably the useful part.

Sent when the figures are re-verified — once a year, near January. Nothing else.

The register

97 thresholds, cited, with drift laws

Every threshold used anywhere in the series lives in one file, exactly once. Renderers ask the datum what it is permitted to do rather than remembering: an index control is physically unable to move a frozen number, and that guarantee is unit-tested.

Drift lawMeaning
FROZENNominal amount with no adjustment mechanism. Moves only by Act of Congress.
INDEXEDRe-set annually by IRS / SSA / CMS / HHS. The stated value will go stale.
SCHEDULEDMoves by a formula written into the statute itself. Not inflation.

Confidence is read as a tolerance band and is never silently promoted. This revision is 94 VERIFIED 1 APPROX 2 UNVERIFIED, and flagged values render with the flag visible. What is unconfirmed about each is listed in the changelog.

The machine-readable snapshot is statutes.json, under CC BY 4.0. The figures themselves are public facts published by the IRS, SSA, CMS and HHS and no claim is made over them — attribution is asked for the compilation: the selection, the drift laws, the confidence flags and the citation trail.

Scope

Scope and limits

Arithmetic, not advice. The charts show their working and name the trade-offs. They are not personalised investment or tax guidance. Talk to a CFP or CPA.

Every dollar figure is approximate and re-indexed. Verify against the current IRS revenue procedure, SSA fact sheet, CMS premium notice and HHS poverty guidelines before relying on any amount.

Nothing here executes anything. No trades, no transfers, no contribution changes.