{"_license": "Reuse with attribution is welcome; copying the work is not. Data (/api/**.json): CC BY 4.0. Charts, share images, embeds and quotes: free to reuse when credited \"History of Market (historyofmarket.com)\" with a link. No derivative or look-alike sites, no use of the brand names, no citation without the source. Terms: https://historyofmarket.com/license/", "_attribution": "History of Market (historyofmarket.com)", "_canonical": "https://historyofmarket.com/api/mag7/concentration.json", "_terms": "https://historyofmarket.com/license/", "updated": "2026-10-03", "source": {"name": "SPY holdings disclosure (live) + curated quarterly history", "method": "M7 share of S&P 500 float-adjusted market cap; latest summed live from SPY holdings, history hand-curated quarterly."}, "note_cn": "M7 在 S&P 500 总市值中的占比演变。最新一点每次自动更新——把 M7 在 SPY ETF 持仓中的权重(已含 float-adjustment 自由流通调整)相加得到,无需复现 S&P DJI 的闭源调整。历史季度点由三家机构的口径交叉核对策展,相互在 0.5 个百分点内一致。", "note_en": "M7 share of total S&P 500 float-adjusted market cap. The latest point auto-updates each run by summing the M7's weights in the SPY ETF's holdings (which already embed S&P DJI's float adjustment) — no need to reproduce the closed float-adjustment process. The quarterly history was cross-checked across three independent estimates, which agree to within ~0.5pp.", "latest": {"date": "2026-10-03", "weight": 33.5, "note": "Live reading — M7 share summed from current SPY ETF holdings, whose weights already embed S&P DJI's float adjustment. Auto-updates every run.", "live": true}, "peak": {"date": "2025-12-31", "weight": 33.5, "note": "Approximate Q4-25 reading; absolute peak so far."}, "series": [{"date": "2018-12-31", "weight": 13.0, "note": "Pre-AI; AAPL/MSFT/AMZN/GOOGL dominate, no NVDA/META leadership yet."}, {"date": "2019-12-31", "weight": 16.0, "note": "Cloud + iPhone rebound year."}, {"date": "2020-12-31", "weight": 22.5, "note": "COVID + work-from-home rally; first time M7 cleared 20%."}, {"date": "2021-12-31", "weight": 24.0, "note": "Peak liquidity era; everything-rally extends concentration."}, {"date": "2022-09-30", "weight": 18.5, "note": "Bear market low — concentration falls back as megacap deflates with everything else."}, {"date": "2022-12-31", "weight": 19.5, "note": "Year-end after the worst Fed hiking cycle in 40 years."}, {"date": "2023-06-30", "weight": 27.0, "note": "ChatGPT/NVDA inflection — M7 contributes ~90% of S&P 500 YTD return."}, {"date": "2023-12-31", "weight": 28.5, "note": "Five of seven hit new all-time highs in Q4."}, {"date": "2024-06-30", "weight": 31.0, "note": "NVDA briefly the world's largest company."}, {"date": "2024-12-31", "weight": 33.0, "note": "Highest single-group concentration in modern US history (since the Nifty Fifty era)."}, {"date": "2025-06-30", "weight": 32.5, "note": "Plateau; some rotation into broader AI ecosystem (semis ex-NVDA, utilities for power)."}, {"date": "2025-12-31", "weight": 33.5, "note": "Approximate Q4-25 reading; absolute peak so far."}, {"date": "2026-03-31", "weight": 32.8, "note": "Latest quarter — slight de-concentration as broader semis and software outperform."}, {"date": "2026-10-03", "weight": 33.5, "note": "Live reading — M7 share summed from current SPY ETF holdings, whose weights already embed S&P DJI's float adjustment. Auto-updates every run.", "live": true}]}