# M7 · Share of S&P 500 Market Cap — Seven Companies, One Third of the Market: S&P 500 Market Cap Share

Source: https://historyofmarket.com/mag7/mag7-concentration/
Language: en
Data through 2026-11-13
License: data CC BY 4.0, text © History of Market — cite "History of Market (historyofmarket.com)" and link the source page. Terms: https://historyofmarket.com/license/
Section: History of Market › Magnificent 7 › Seven Companies, One Third of the Market: S&P 500 Market Cap Share

Mag 7 share of the S&P 500: 33.2% as of 2026-11-13.

**Magnificent 7 Market Cap Share** — Combined weight of the Magnificent 7 within the S&P 500, approaching peak concentration levels of the 1970s Nifty Fifty.

Figure: Plate VII.2 · The combined share of S&P 500 market capitalization rose from 13% in 2018 to over 33% by year-end 2024, marking the highest concentration in market leaders since the Nifty Fifty era of the early 1970s. · Data through 2026-11-13

## Latest Snapshot

- **Observations** — 14
- **Sample** — 2018-12-31 – 2026-11-13

## What this page answers

The Magnificent Seven (AAPL, MSFT, NVDA, GOOGL, AMZN, META, TSLA) have expanded from 13.0% of S&P 500 market capitalization in 2018 to 33.2% as of 2026-11-13 (live summation of index weights) — establishing the highest concentration in seven mega-cap leaders since the Nifty Fifty era of the early 1970s.

The data is refreshed by the History of Market pipeline and published as a stable JSON endpoint for research, citation, and AI-agent use.

## Magnificent 7 aggregate share of S&P 500 market capitalization (quarterly)

| Date | Weight |
| --- | --- |
| 2026-11-13 | 33.2% |
| 2026-03-31 | 32.8% |
| 2025-12-31 | 33.5% |
| 2025-06-30 | 32.5% |
| 2024-12-31 | 33.0% |
| 2024-06-30 | 31.0% |
| 2023-12-31 | 28.5% |
| 2023-06-30 | 27.0% |
| 2022-12-31 | 19.5% |
| 2022-09-30 | 18.5% |
| 2021-12-31 | 24.0% |
| 2020-12-31 | 22.5% |
| 2019-12-31 | 16.0% |
| 2018-12-31 | 13.0% |

Complete record (14 rows). Raw dataset: https://historyofmarket.com/api/mag7/concentration.json

## Data & Source

[GET /api/mag7/concentration.json](https://historyofmarket.com/api/mag7/concentration.json) — Canonical dataset endpoint.

Exchange closing prices · Company filings · Robert Shiller · FRED · NBER.

## FAQ

### What percentage of the S&P 500 do the Magnificent 7 represent today?

33.2% as of 2026-11-13, up dramatically from 13.0% in 2018.

### 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 each weekend. 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.

## Related charts and reading

- [Cash Flow Divergence: AI Infrastructure Capex vs. Shareholder Returns](https://historyofmarket.com/mag7/mag7-ai-capex/)
- [Nasdaq vs S&P 500: 40 Years of Returns, Drawdowns and Valuation](https://historyofmarket.com/articles/nasdaq-vs-sp500)
- [Magnificent 7 Weight in the S&P 500: 33% and Counting](https://historyofmarket.com/articles/magnificent-7-sp500-weight)
- [S&P 500 100-Year Returns: Annual Returns by Year, CAGR & Worst Years (1928–2026)](https://historyofmarket.com/articles/sp500-100-year-returns)

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Data: https://historyofmarket.com/api/mag7/concentration.json
Machine index: https://historyofmarket.com/llms.txt