How Frequently Should You Change Your Lifetime Planning Period Assumptions?

Assumptions
regarding how long you and your spouse, if you have one, plan to
survive in retirement are central to determining your funded status.
These assumptions — your lifetime planning period assumptions (LPPs)
— define the horizon over which assets must support spending. The
Actuarial Financial Planner (AFP) model on our website includes default
LPPs based on the ages entered and planning horizons from the 2022
Actuaries Longevity Illustrator, using the 25% chance‑of‑survival metric
for non‑smokers in excellent health.In our January 20, 2026 Advisor Perspectives article and our January 24, 2026 post, we
encouraged readers to develop more personalized LPPs using a three‑step
process. This process uses results from various life‑expectancy
calculators to estimate an age adjustment reflecting your specific
health and habits (your “biological age” vs. your chronological age) and then applies the Longevity Illustrator’s 25% survival horizon for
that adjusted age. Inputting these personalized LPPs into the AFP
generally requires using the override process described in the workbook.
It is important to follow this override process rather than simply
changing the LPP in column H of the spreadsheet.Why LPPs Should Be Updated RegularlyA natural question is: How frequently should you change your LPP assumptions? We recommend updating them at least once a year
as part of your regular valuation cycle. While LPPs will often decrease
by one year as you age, they do not always move linearly. Annual
updates help ensure that your funded status reflects:The alignment of chronological age and biological ageChanges in personal health, habits, or functional statusMortality improvement embedded in population tablesThe evolving financial needs of both spousesWithout periodic recalibration, funded‑status measures can drift away from reality, reducing their usefulness for planning.When More Significant Adjustments Are NeededIn
addition to annual updates, certain events warrant a more substantial
revision of your LPPs. Each year, we encourage you to repeat the
three‑step biological‑age process. But if you or your spouse experience a
meaningful change in health or habits, a larger adjustment may be
appropriate.Examples include:A cardiac event or strokeA cancer diagnosisA mobility‑limiting conditionA significant decline in functional capacityA major change in habits (e.g., quitting smoking, substantial weight loss, or conversely, adopting less healthy behaviors)These
events can shift biological age by several years, and therefore may
reduce (or occasionally increase) the appropriate LPP by more than the
usual one‑year decrement.When one spouse experiences a negative
health event, additional planning may be required for the other spouse. A
shortened LPP for one member of the couple may imply:Earlier survivor‑spending recalibrationIncreased near‑term medical or caregiving expensesRevised long‑term‑care contingenciesAdjustments to survivor Social Security timing or benefit expectationsThese considerations highlight why LPPs should be treated as dynamic assumptions rather than static parameters.SummaryLPPs are a foundational input to funded‑status calculations and should be updated at least annually.Use the three‑step biological‑age process each year to maintain alignment between personal health and planning horizons.Significant health or habit changes may require larger, non‑linear adjustments to LPPs.When
one spouse experiences a negative health event, revisit both spouses’
LPPs and consider the broader financial and caregiving implications.Always use the AFP override process to ensure updated LPPs flow correctly through the model.