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The Archive / from facts to structure

TheMethod

Seven phases. Four pillars.
One retirement structure.

Datumae organizes a retirement-planning question so its facts, pressures, assumptions, and choices can be examined together.

The Studio process / Datumae

A question becomes
a structure to examine.

The method moves from what is known, through what can apply pressure, toward a measured Range—and into the decisions and reviews that carry the structure forward.

[ D + A ] × [ T + U ] = M → [ A + E ]

A framework for organizing inputs, pressures, modeled results, and decisions—not a prediction or prescription.

01 / Inputs

You bring

Household facts, choices, and assumptions.

02 / Organization

Datumae organizes

The Estate, loads, uncertainty, and model settings.

03 / Outputs

The method reveals

A Range, trade-offs, and questions to revisit.

The complete system

Seven phases.
One connected method.

Follow the work in order, or return to the phase you want to understand. The details remain close to each part of the structure.

Pillar / BUILD IT

Establish the Estate.Begin with the household, then define the structure around it.

PHASE 01Establish the Baseline.

Data

Establish the household, planning horizon, and starting facts before interpretation begins.

Household / years / starting facts
Inputs, workspaces & limits
What enters

Date of birth, target retirement date, plan-through date, gross annual salary, how that salary is expected to rise, filing status, and retirement location. Individual uses seven core Profile fields. Joint uses twelve: birth date, retirement date, plan-through date, salary, and expected pay rise for each person, plus one shared filing status and one shared retirement location.

What Datumae organizes

A consistent starting point and the time relationships that later phases will use.

What emerges

A clear starting point: who the plan is for, the years it covers, and the tax assumptions it begins with.

What it does not decide

Whether the supplied facts are complete or whether a household's current choices should remain unchanged.

Plan ConfigurationHousehold timing and scopeArchitect ProfileSolo or Joint household facts
PHASE 02Define the Mass.

Architecture

Turn the baseline into an Estate: the accounts, assets, property, income, and contribution flows that can fund retirement.

Accounts / assets / contribution flow
Inputs, workspaces & limits
What enters

Account and asset balances, property, income sources, contribution patterns, retirement timing, and the initial Target Spending selected in Retirement Baseline.

What Datumae organizes

Capital by account type, funding sources, contribution plumbing, Target Spending, and the transition from accumulation to retirement.

What emerges

A financial floor plan. Retirement Baseline is an early architectural study within this broader Studio journey.

What it does not decide

Which account, asset, contribution level, Target Spending, or retirement date a household should choose.

Retirement BaselineInitial retirement structureEstate DraftingAccounts, assets, and incomeContribution PlumbingSavings flows into the Estate
Pillar / TEST IT

Apply the Pressure.Separate the loads the Estate carries from the uncertainty around them.

PHASE 03Apply the Pressure.

Tension

Make visible the spending, debts, and obligations that place continuing load on the Estate.

Committed / chosen / changing loads
Inputs, workspaces & limits
What enters

Debts, living expenses, recurring obligations, discretionary spending, giving, duration, and planned changes over time.

What Datumae organizes

Committed and chosen loads, when they begin or end, and where released cash flow may be redirected.

What emerges

A load map showing what the Estate is being asked to support and when that pressure changes.

What it does not decide

Which debts, lifestyle priorities, gifts, or obligations a household should retain, reduce, or remove.

Committed LoadsRequired spending and obligationsChosen LoadsLifestyle spending and prioritiesLoad RoutingTiming, duration, and redeployment
PHASE 04Structure the Noise.

Uncertainty

Name the forces no one can know in advance, and give each one an explicit, changeable assumption.

Inflation / healthcare / pension
Inputs, workspaces & limits
What enters

Two inflation rates: the economy’s, and how much faster healthcare rises. Each person’s healthcare cost before Medicare, after 65, and for later-life care. For a pension: its amount, when it starts, what continues to a survivor, and how it adjusts each year.

What Datumae organizes

Where each assumption enters the plan, who it belongs to, and how it changes across the years, including after one person’s horizon ends.

What emerges

A visible set of uncertainty assumptions, each labeled as yours or as Datumae’s sourced default, and each one you can change and test.

What it does not decide

What inflation, healthcare costs or longevity will actually be, or which pension election is right for you.

Inflation PerimeterPurchasing-power assumptionsHealthcare DrainageMedicare and late-life costsPension TrussTiming and survivor options
Pillar / SHAPE IT

Reveal the Range.Use defined assumptions and model settings to examine how the structure can behave.

PHASE 05Reveal the Range.

Measurement

Examine the assembled Estate under defined model settings, fixed stress cases, and alternative spending lines.

Ceiling / Spending / Floor
Inputs, workspaces & limits
What enters

The built Estate, loads, uncertainty assumptions, Social Security claiming choices, market model design, and the spending line selected for examination.

What Datumae models or reveals

Fixed stress-case survival, modeled-path behavior, sensitivity, and the relationship among Ceiling, Spending, and Floor.

What emerges

A Range, visible trade-offs, and questions that may send the household back to an earlier phase.

What it does not decide

A guaranteed spending level, a prediction, an investment recommendation, or a universal answer.

Climate ControlModel design and sensitivitySocial Security CanopyClaiming ages and household benefitsSystems PanelStress cases and model settings

MEASUREMENT / RANGE

How the Range Is Formed

The Range gives distinct jobs to a stress-informed lower boundary, a household-selected spending line, and an upper modeled band. Follow the visual guide to the Range →

Estate / Spending Reference

Illustrative Scenario
Conceptual relationship only. The three lines serve different purposes and should not be read as equal statistical boundaries.

Boundary definitions

Ceiling
An upper modeled spending band under more favorable modeled conditions. It is not a promise of what markets or a plan will deliver.
Spending
The household's selected lifestyle line being examined against the Estate, assumptions, and Range. It is a planning input, not a mathematical boundary.
Floor
A lower planning boundary informed by the defined stress battery selected for the analysis. It is not a guarantee and not a universal safe-spending rule.

A Range is not an answer handed down by a model. It is a structured way to see the trade-offs created by the facts, choices, and assumptions being tested.

SECONDARY TECHNICAL DETAIL

Model Design

A modeled path is one simulated sequence of market and economic conditions used to examine how a retirement structure could behave under stated assumptions. Model Design shapes the modeled findings; fixed stress replays form the Floor. Neither is a forecast of what will happen.

Datumae Blend

40,000

Four distinct lenses run at 10,000 paths each, then combine into the Datumae reference design.

Parametric

10,000

A statistical lens that generates many possible return paths from defined distribution assumptions.

Historical

10,000

A lens that examines paths informed by observed historical market sequences.

CAPE-Adjusted

10,000

A valuation-sensitive lens that adjusts starting conditions using market valuation context.

Regime

10,000

A lens that examines paths across persistent market and inflation environments.

Model Methodology & Assumptions

Datumae Blend

Runs Parametric, Historical, CAPE-Adjusted, and Regime at 10,000 paths apiece—40,000 modeled paths across four separate lenses. Blend weights each lens’s answer equally at each rung; it does not pool the paths into one distribution.

Parametric Log-Normal

Runs 10,000 modeled paths using dynamically calculated drift and volatility. It assumes returns follow a log-normal distribution, providing a baseline spectrum of mathematical probabilities.

Historical (1926–2025)

Runs 10,000 modeled paths by sampling observed U.S. market years one at a time. The size of an observed year is retained, but its original chronological order is not.

CAPE Valuation Adjustment

Runs 10,000 modeled paths with baseline expectations adjusted by the starting Shiller PE ratio. When markets begin from historically elevated valuations, the design applies a reversion-to-mean adjustment to future returns.

Regime Bootstrap

Runs 10,000 modeled paths by selecting contiguous multi-year blocks, preserving prolonged periods of stagnation, inflation, or supportive conditions rather than treating each year independently.

The Stress Battery

Sets the Floor with five fixed stress cases rather than a Monte Carlo percentile: the 1929 Great Depression, the 1966 Great Inflation, the 2000 dot-com bust, the 2007 financial crisis, and a constructed twelve-year stagflation. The Systems Panel controls how many of the five the Floor must survive.

Floor is separate from modeled-path percentiles. It is informed by the defined fixed stress battery selected for the analysis.

Results are modeled illustrations, not predictions, guarantees, investment recommendations, or personalized financial advice.

SENSITIVITY MAP

What Changes the Result

A Range belongs to the specific facts, choices, and assumptions used to form it. Change the structure and the result can change with it.

01 / TIME

Time

Current age, retirement timing, longevity horizon, and when income, spending, or obligations begin and end.

02 / INCOME

Income

Earnings, pension income, Social Security choices, structured income, and their timing.

03 / SPENDING

Spending

The lifestyle line being tested, committed loads, chosen loads, one-time spending, and later-life changes.

04 / ESTATE

Estate

Accounts, assets, property, debt, contributions, liquidity, and how capital is distributed across the structure.

05 / TAX ASSUMPTIONS

Tax assumptions

Account treatment, taxable income assumptions, rates, and the way funding layers are represented for comparison.

06 / UNCERTAINTY

Uncertainty

Inflation, healthcare, longevity, market design, volatility, and the timing of events that cannot be known in advance.

Pillar / LIVE IT

Order and Carry the Plan.Make decision points visible, then define when the work should be reopened.

PHASE 06Order the Estate.

Alignment

Make the relationship among account types, funding layers, and withdrawal-order assumptions visible for comparison.

Taxable / pre-tax / tax-free layers
Inputs, workspaces & limits
What enters

The Estate, expected income, spending needs, account rules, and household-selected funding assumptions.

What Datumae organizes

Accumulation structure and possible taxable, pre-tax, and tax-free funding layers across time.

What emerges

Comparable funding and withdrawal-order assumptions whose effects can be examined against the wider structure.

What it does not decide

A best withdrawal order, a personalized tax strategy, or a promised tax outcome.

Account FormationAssets organized by account typeWithdrawal LayersFunding-order assumptions
PHASE 07Carry the Horizon.

Endurance

Carry the spending question across the retirement horizon and establish when the structure should be reviewed.

Spending path / review / reopen
Inputs, workspaces & limits
What enters

Target Spending, the modeled Arc, the Range, stress results, household guardrails, and material changes since the last review.

What Datumae organizes

The spending path, tuning questions, stress comparisons, review guardrails, and a maintenance plan.

What emerges

A documented set of conditions for revisiting earlier phases—not an assumption that the plan will adapt itself.

What it does not decide

When a household must change spending, how markets will develop, or whether any plan will endure unchanged.

Datum BuilderTarget Spending and guardrailsArc HorizonCeiling, Spending, and Floor over timeTuning PassAccount fit and refinementsUnder StressRange behavior under pressureMaintenance PlanReview triggers and reopen points

TRANSPARENCY

Modeled. Held Constant. Chosen.

The method is clearer when every element has a visible role—and when the limits are recorded beside the result.

Element
Role in the method
Limit
Household facts
Describe the people, timeline, Estate, income, and obligations entering the analysis.
Only as current and complete as the information supplied.
Household choices
Set the retirement timing, spending line, claiming choices, and alternatives being compared.
Remain choices; the method does not convert them into prescriptions.
Model settings
Define the economic and market assumptions used to produce modeled paths.
Describe an analytical design, not the future.
Fixed stress cases
Apply defined adverse sequences to inform the Floor under the selected survival requirement.
Do not contain every possible adverse event and are not Monte Carlo percentiles.
Modeled outcomes
Reveal distributions, sensitivities, trade-offs, and the upper modeled band.
Are illustrations, not predictions, guarantees, or recommendations.

When to Reopen the Plan

Endurance is a review discipline. Reopen the relevant phases when the structure changes enough that its earlier assumptions no longer describe the same question.

01 / TIMING

Retirement begins materially earlier or later than planned.

02 / SPENDING

Recurring or one-time spending changes materially.

03 / INCOME

Pension or Social Security amounts, timing, or elections change.

04 / ESTATE

Accounts, property, debt, contributions, or income change materially.

05 / LIFE

Health, longevity, household, or family circumstances change.

06 / CONDITIONS

Market or economic conditions create a new scenario the household wants to test.

The method becomes work

Bring the question into Studio.

Studio is where the seven-phase method becomes a working financial Estate. Explore an idea at the Drafting Table, or read the principles behind the system.

Enter the StudioStart at the Drafting TableRead the Philosophy