Nvidia accounted for 15.5% of the S&P 500's total return in 2025, with projected Q4 revenue of $65.7B. Here's what that concentration means for investors.

Nvidia accounted for 15.5% of the S&P 500's total return in 2025, with projected Q4 revenue of $65.7B. Here's what that concentration means for investors.

S&P 500 and NASDAQ Composite are heading into a crucial week near record highs, with investors focused on two key themes — the AI-driven market rally and the strength of U.S.…