Assumptions and planning policy
Edit Planning Assumptions
Choose fixed or historical growth and inflation assumptions for the deterministic retirement projection.
Choose one return basis for the deterministic projection
Planning Assumptions controls the economic path used by Projection and other deterministic comparisons. Fixed rates apply one expected nominal growth rate and one inflation estimate. Historical data instead uses the supported asset-class and inflation observations from a historical window ending in the selected year.
Neither choice predicts the future. Fixed rates make the assumption easy to see and vary; historical data preserves an observed sequence and its ordering. Use the mode that fits the question, then keep it unchanged when comparing another decision.
Fixed growth and inflation should describe the same nominal world
Expected portfolio growth is one annual nominal return, before subtracting inflation, applied to stock, bond, and cash holdings in a fixed-rate Projection. New plans start at 6%. Inflation is the annual increase applied to expenses and other inflation-linked amounts unless a more specific override exists. A lower growth estimate or higher inflation estimate generally makes the plan more demanding, but the effect depends on taxes, cash flows, and asset timing.
Use assumptions you can explain rather than tuning the rates until a desired result appears. If the decision depends on a narrow range, compare clearly labeled What-if scenarios instead of replacing the Home plan repeatedly.
Historical mode pins a reproducible ending year
The Shared historical end year selects the last observation used by the supported historical series. The chosen year remains pinned when newer reference years become available, which prevents a saved comparison from changing merely because the reference library was updated.
Historical mode drives growth and inflation from the historical data, so the fixed Expected portfolio growth and Inflation estimate are not active. Moving the end year changes the sequence being tested and should be treated as a different assumption, not as a routine data refresh.
Stochastic Analysis has its own return and inflation settings
The deterministic Expected portfolio growth field is not the stock mean for Stochastic Analysis. Stochastic Analysis starts with separate 7% stock, 4% bond, and 3% cash means and separately stores volatilities, correlations, inflation, and other settings. A zero-volatility stochastic run can still differ from Projection when those asset-class means differ.
After saving, rerun Projection and check that the selected mode is named with the result. Rerun Stochastic Analysis only when you also intend to review or change its own saved parameters.