An intergenerational spending policy built around depletion risk, not expected return

Expected return is not a spending guarantee

Mork, Trønnes and Bjerketvedt simulate the Norwegian Government Pension Fund Global and discuss parallels with endowments. Their model shows why drawing an amount equal to expected return does not guarantee survival. The result depends on a sovereign-fund setting, specified return and fiscal processes, currency effects and historical estimates. A family office should not copy its parameters or treat the article as a personalized withdrawal recommendation.

The practical lesson is to govern distributions through a range of adverse paths, not a single average. Spending, taxes, capital calls, philanthropy, operating-company needs and beneficiary liquidity can arrive when markets or currencies are unfavorable. The office must define which commitments are fixed, which can adjust and who has authority to change them.

Map liabilities and currencies before setting a rule

The chief financial officer maintains a rolling map of expected distributions, taxes, debt service, capital calls, charitable commitments, insurance premiums and operating reserves. Each item has timing, currency, legal priority, adjustability and an accountable owner. Contingent claims are shown separately from approved commitments.

The investment office maps assets by liquidity, currency, valuation frequency and restrictions. It does not count an appraisal as executable cash or assume a private fund can be redeemed. Currency exposure is measured against the currencies of actual spending. The board receives both gross wealth and readily available liquidity after haircuts and committed obligations.

Run transparent scenarios rather than a magic rate

The risk lead models multiple horizons and return paths, including early losses, sustained inflation, currency shifts, private-asset write-downs, delayed exits and simultaneous capital calls. Assumptions, data dates, fees, taxes and rebalancing rules are versioned. Results show distributions, liquidity shortfalls and depletion probabilities or ranges without presenting simulation precision as certainty.

The board tests candidate policies: fixed real spending, percentage-of-assets rules, multi-year smoothing, floors and caps, reserve funding and temporary reductions. It examines who bears adjustment under each rule. A lower simulated depletion risk does not settle questions of fairness, beneficiary rights or mission; those require separate governance and legal review.

Define authority for exceptions

The distribution policy identifies routine authority, emergency authority, required evidence, recusal and the body that can approve an exception. An exception states amount, source of liquidity, affected commitments, restoration plan and review date. Repeated exceptions are treated as a policy failure signal rather than normalized through informal precedent.

Trustees and directors receive a dashboard that separates market loss, spending, taxes, fees, currency and valuation changes. The record preserves dissent and the evidence available at the time. Beneficiary communications explain the rule and uncertainty within lawful disclosure boundaries; they do not promise that wealth will be preserved indefinitely.

Measures, reviews and stopping conditions

Measures include months of liquid coverage, unfunded commitments, spending as a percentage of liquid and total assets, concentration, currency mismatch, policy exceptions, scenario shortfalls and time to execute a liquidity response. The board reviews assumptions at least annually and after material portfolio, family, tax or legal changes. Independent validation tests calculations and source data.

Discretionary distributions pause when required liquidity falls below the approved floor, asset values are stale beyond policy, an exception lacks authority, capital calls are unfunded or scenarios rely on an unverified expected-return input. Emergency obligations follow their separate lawful process. The office records the pause, affected parties and remediation. Neither the study nor this protocol proves a safe rate or guarantees intergenerational preservation.

Connect the policy to investment implementation

The chief investment officer documents how the distribution policy affects strategic liquidity, rebalancing bands, currency hedging, commitment pacing and permitted leverage. The investment team does not raise expected-return assumptions to make an unaffordable spending rule appear sustainable. Changes to portfolio risk and changes to spending are presented separately so the board can see which lever carries the burden.

Quarterly reporting reconciles opening assets, contributions, distributions, fees, taxes, market change, currency effects, valuation change and closing assets. Private valuations carry dates and uncertainty flags. If an asset cannot be sold or borrowed against within the policy horizon, it is excluded from executable liquidity. This reconciliation lets trustees identify whether repeated shortfalls arise from markets, commitments, assumptions or governance exceptions.

Source, attribution and limits

[1] Knut Anton Mork; Haakon Andreas Trønnes; Vegard Skonseng Bjerketvedt. Capital Preservation and Current Spending with Sovereign Wealth Funds and Endowment Funds: A simulation Study. International Journal of Financial Studies (2022-08-11). https://doi.org/10.3390/ijfs10030067. CC BY 4.0.

The model centers on Norway’s sovereign fund, uses historical 1991–2020 financial data, normal innovations and specified fiscal variables. It is not a family-office backtest or forecast, omits some tail behavior and cannot determine a universal safe withdrawal rate for a particular family, currency, tax system or portfolio.

Prepared by the Family Office Private Wealth Journal editorial research desk with AI assistance at the direction of Dr. Freedom Cheteni. Original research authors retain full credit and are not authors or endorsers of this companion. This proposed process has not been evaluated in a new empirical study; no independent peer-review acceptance is claimed. This is educational analysis, not individualized investment, legal or tax advice.

Implementation record

Open the cited sources

1. [1] Knut Anton Mork; Haakon Andreas Trønnes; Vegard Skonseng Bjerketvedt. Capital Preservation and Current Spending with Sovereign Wealth Funds and Endowment Funds: A simulation Study. International Journal of Financial Studies (2022-08-11). ↗