S&P 500 · Multiplicative Contribution by Extreme Days — Do Not Add Returns, Ask What Each Group Multiplies
Extreme days — Miss the best (or dodge the worst) few dozen days and see what compounding does.
[Ex-post accounting, not timing advice] The five groups multiply, not add: best 50 days ×13.37, middle ≈6,500 days ×1.80, worst 30 days ×0.15, and $1 ends at $5.10.
What this page answers
This static page is built to answer searches for S&P 500 · Multiplicative Contribution by Extreme Days. It summarizes the live dataset behind the Do Not Add Returns, Ask What Each Group Multiplies panel and links to the full interactive chart.
[Ex-post accounting, not timing advice] The five groups multiply, not add: best 50 days ×13.37, middle ≈6,500 days ×1.80, worst 30 days ×0.15, and $1 ends at $5.10. The data is refreshed by the History of Market pipeline and published as a stable JSON endpoint for research, citation, and AI-agent use.
The plate
Latest Snapshot
- Updated
- 2026-09-03
Data & Source
GET /api/sp500/daily-extremes.json — Canonical dataset endpoint.
Exchange closing prices · Company filings · Robert Shiller · FRED · NBER.
FAQ
Where does this data come from?
History of Market combines public market and macro datasets — exchange closing prices, company filings, Robert Shiller, FRED, NBER, and the UBS Global Investment Returns Yearbook (Dimson–Marsh–Staunton). The exact endpoint for this panel is linked below.
How often is it updated?
Daily-tier datasets refresh after the U.S. market close, with a broader weekly refresh on Sunday. The timestamp shown on this page comes from the JSON payload.
Can I use the data?
Yes, for research and education with attribution to History of Market. Upstream data sources retain their own terms.