According to The Kobeissi Letter, Nvidia’s (NVDA) weight in the S&P 500 has reached a record 8.2%, more than doubling since the start of 2024, as its market value hit $4.4 trillion last week, signaling unprecedented single-name concentration at the index level, source: The Kobeissi Letter (X, Aug 16, 2025). Because the S&P 500 is float market-cap weighted, a higher NVDA weight mechanically increases passive index allocation and can amplify NVDA-driven index moves, source: S&P Dow Jones Indices, S&P 500 Index Methodology. For crypto traders, equity risk is a key input: the IMF documented a stronger return correlation between BTC and the S&P 500 during 2020–2022, indicating that large S&P swings led by mega-caps can coincide with BTC and ETH volatility, source: International Monetary Fund, 2022 analysis on crypto–equity co-movements.