Data Sources

Historical datasets used

We use long-run academic and market datasets to model UK, US, and global asset returns. This page summarises the sources in plain language.

Equities

  • UK equities: Jordà-Schularick-Taylor (JST) UK series.
  • US equities: Shiller S&P 500 total return series.
  • Global equities: JST global proxy (1871–2000) and MSCI World GBP (2001–present).

Bonds

  • UK bonds: JST UK government bonds.
  • Global bonds: JST global bonds (1871–2000) and IGLO/AGGG proxy (2001–present).

Inflation

  • UK inflation: UK CPI series (JST).

Proxy transitions

Some series use a historical dataset up to a cutover point and a modern index after that. We do not blend overlapping years. The tool uses clean switch points and shows the actual data window used in results.

Related links

Run the calculator, review methodology, or explore the FAQ for assumptions and definitions.

Last updated: 2026-02-23