The Long Term Investor

Vanguard's Return Forecasts Explained: What the Percentiles Really Mean with Kevin DiCiurcio (EP.241)

Jan 28, 2026
Kevin DiCiurcio, head of Vanguard's Capital Markets Model development and research lead, explains how Vanguard builds and governs its long‑term return forecasts. He breaks down what percentiles mean, contrasts 10‑year versus 30‑year outlooks, and discusses implications for asset allocation, megatrends like AI, and the signals that would change Vanguard's views.
Ask episode
AI Snips
Chapters
Books
Transcript
Episode notes
INSIGHT

Blend Predictability With Explainable Drivers

  • VCMM blends predictability from starting valuations with explainable income and valuation-change components.
  • Vanguard avoids ad-hoc sum-of-parts overlays by modeling these drivers holistically and systematically.
ADVICE

Read Percentiles As Probabilities, Not Predictions

  • Interpret percentiles as probabilities: e.g., the 25th–75th range has a 50% chance of containing realized 10-year returns.
  • Treat the median at ~10-year horizons as a useful return expectation; avoid over-interpreting shorter-term medians.
ANECDOTE

2022 Drawdown Was Within VCMM's Tail

  • Vanguard reviewed 2022 and found the model projected a 19% drawdown for a 40/60 US portfolio as of December 2021 conditions.
  • That realized severe simultaneous losses in stocks and bonds sat near the model's 95th percentile of max drawdowns.
Get the Snipd Podcast app to discover more snips from this episode
Get the app