| Year | Sector | Weight (%) | YoY Change | Top Company |
|---|---|---|---|---|
| 2026 | Information Technology | 31.96% | +0.83% | Nvidia |
| 2026 | Financials | 12.48% | +0.41% | Berkshire Hathaway |
| 2026 | Communication Services | 11.39% | +0.06% | Alphabet Inc. (Class A) |
| 2026 | Consumer Discretionary | 10.47% | -0.09% | Amazon |
| 2026 | Health Care | 9.33% | -0.78% | Lilly (Eli) |
| 2026 | Industrials | 8.74% | +0.12% | GE Aerospace |
| 2026 | Consumer Staples | 5.91% | -0.18% | Walmart |
| 2026 | Energy | 3.49% | +0.16% | ExxonMobil |
| 2026 | Utilities | 2.42% | -0.18% | NextEra Energy |
| 2026 | Materials | 1.92% | -0.18% | Linde plc |
| 2026 | Real Estate | 1.88% | -0.19% | Welltower |
| 2020 | Information Technology | 27.00% | +1.00% | Nvidia |
| 2020 | Health Care | 14.00% | +0.17% | Lilly (Eli) |
| 2020 | Consumer Discretionary | 11.00% | +0.25% | Amazon |
| 2020 | Communication Services | 11.00% | +0.67% | Alphabet Inc. (Class A) |
| 2020 | Financials | 10.00% | -0.25% | Berkshire Hathaway |
| 2020 | Industrials | 8.00% | -0.25% | GE Aerospace |
| 2020 | Consumer Staples | 7.00% | -0.33% | Walmart |
| 2020 | Utilities | 3.50% | -0.04% | NextEra Energy |
| 2020 | Materials | 3.00% | -0.08% | Linde plc |
| 2020 | Real Estate | 3.00% | -0.08% | Welltower |
| 2020 | Energy | 2.50% | -1.04% | ExxonMobil |
| 2008 | Information Technology | 15.00% | -2.25% | Microsoft / Cisco |
| 2008 | Energy | 15.00% | +1.25% | ExxonMobil |
| 2008 | Financials | 13.00% | 0.00% | Citigroup / AIG |
| 2008 | Health Care | 12.00% | +0.25% | Lilly (Eli) |
| 2008 | Industrials | 11.00% | +0.12% | GE Aerospace |
| 2008 | Consumer Staples | 11.00% | +0.37% | Walmart |
| 2008 | Consumer Discretionary | 8.00% | -0.50% | Walmart / Home Depot |
| 2008 | Utilities | 4.00% | +0.25% | NextEra Energy |
| 2008 | Materials | 4.00% | +0.12% | Linde plc |
| 2008 | Real Estate | 4.00% | +0.50% | Welltower |
| 2008 | Communication Services | 3.00% | -0.13% | Alphabet Inc. (Class A) |
| 2000 | Information Technology | 33.00% | 0.00% | Microsoft / Cisco |
| 2000 | Financials | 13.00% | 0.00% | Citigroup / AIG |
| 2000 | Consumer Discretionary | 12.00% | 0.00% | Walmart / Home Depot |
| 2000 | Health Care | 10.00% | 0.00% | Lilly (Eli) |
| 2000 | Industrials | 10.00% | 0.00% | GE Aerospace |
| 2000 | Consumer Staples | 8.00% | 0.00% | Walmart |
| 2000 | Energy | 5.00% | 0.00% | ExxonMobil |
| 2000 | Communication Services | 4.00% | 0.00% | Alphabet Inc. (Class A) |
| 2000 | Materials | 3.00% | 0.00% | Linde plc |
| 2000 | Utilities | 2.00% | 0.00% | NextEra Energy |
| 2000 | Real Estate | 0.00% | 0.00% | Welltower |
Showing key pivot years (2000, 2008, 2020, 2026). Full dataset available via API.
The rise of mega-cap tech stocks (often referred to as the "Magnificent Seven") driven by cloud computing, mobile, and most recently artificial intelligence, has caused the Information Technology and Communication Services sectors to swell. As of 2026, IT alone commands over 31.9% of the index.
In 2008, driven by oil prices exceeding $140 per barrel, the Energy sector peaked at over 15% of the S&P 500. A subsequent decade of increased supply (US shale boom) and a shift towards renewables caused the sector's weight to collapse to roughly 2.5% by 2020, before recovering slightly.
The S&P 500 index rebalances quarterly, usually in March, June, September, and December. During these rebalances, companies may be added or removed, and shares outstanding are updated, which affects sector weights.
This study analyzes the sector composition of the S&P 500 index. Current year (2026) data is scraped and aggregated from active index constituent lists. Companies are categorized according to the Global Industry Classification Standard (GICS). Historical data (2000-2025) is modeled based on documented market capitalizations and sector compositions at key historical anchor points (such as the 2000 tech bubble and 2008 financial crisis) and interpolated for illustrative trend visualization. Real Estate was carved out of Financials into its own GICS sector in 2016, which is reflected in the historical fade-in.
Westmount Fundamentals. "S&P 500 Sector Weights: The 25-Year Rotation (2000-2026)." westmountfundamentals.com/sp500-sector-weights, 2026.