Research dataset
Online Data: U.S. Stock Markets 1871–Present ↗
Robert J. Shiller, Yale University
Used for: Historical context for return and inflation sensitivity ranges. The calculator does not import this dataset or forecast from it.
Evidence register
Data sources and how we use them
These references provide context for assumptions or rules used in specialized tools. The core Coast FIRE calculator calculates from the values you enter and does not pull live market data.
How to read this page
A citation explains a number or range; it is not an endorsement and does not turn a historical average into a forecast. Rules, limits and prices can change. Follow the source link before acting on year-sensitive information.
Core model context
Official statistics
Consumer Price Index databases ↗
U.S. Bureau of Labor Statistics
Used for: Historical context for inflation scenarios. The inflation input remains entirely user controlled.
Original research
Determining Withdrawal Rates Using Historical Data ↗
William P. Bengen, Journal of Financial Planning (1994)
Used for: Background for the 4% rule of thumb. It does not guarantee that 4% will work for a particular retirement.
Original research
Retirement Savings: Choosing a Withdrawal Rate That Is Sustainable ↗
Cooley, Hubbard and Walz (1998)
Used for: Historical withdrawal-rate context across portfolio mixes and retirement periods.
Industry research
Trends in the Expenses and Fees of Funds, 2025 ↗
Investment Company Institute
Used for: Context for testing the effect of different annual investment-fee assumptions.
Rules and specialized calculators
Official rules
Retirement-plan contribution limits ↗
Internal Revenue Service
Used for: Reference for year-specific U.S. contribution limits. Users should check the displayed tax year.
Official rules
Inflation-adjusted tax items by tax year ↗
Internal Revenue Service
Used for: Reference for year-specific federal tax thresholds in tax-related tools.
Official estimator
Get a benefits estimate ↗
U.S. Social Security Administration
Used for: Preferred source for a personalized Social Security estimate; site tools remain simplified comparisons.
Official marketplace
Marketplace plans and estimated prices ↗
HealthCare.gov
Used for: Preferred source for location-specific marketplace prices; health-cost tools are planning estimates.
Source selection and maintenance
Preference order
Official government material and original research come first. Institutional research supports areas where no government source applies.
Freshness
Year-sensitive inputs should name their applicable year. We check linked sources when a related calculator changes.