EquitiesS&P Dow Jones IndicesContinuous

S&P 500 Index

What is S&P 500 Index?

Market-cap weighted index of 500 large U.S. companies.

Why it matters

The benchmark for U.S. equity performance.

How to read prints

When it rises

Risk-on; equity valuations expanding.

When it falls

Risk-off; equity valuations compressing.

Frequently asked

What is the S&P 500?
A market-cap-weighted index of 500 of the largest U.S. publicly traded companies. It is the standard U.S. equity benchmark.
What is the difference between SPX, SPY, and ES?
SPX is the index; SPY is the State Street ETF tracking it; ES is the CME E-mini S&P 500 futures contract.
What is a typical S&P 500 P/E ratio?
The long-run forward P/E averages around 16-17x. Above 20x is rich; below 14x is cheap.
How concentrated is the index?
The top 10 names account for ~35% of market cap as of 2024, the highest concentration since the 1970s.

Track it on Market Ontology

Monitor S&P 500 Index in real time on Overview / Macro Regime Dashboard, alongside regime classification, transmission mapping, and cross-asset context.

SourceS&P Dow Jones Indices
FrequencyContinuous
CategoryEquities
FRED SeriesSP500
Unitindex
Related ModuleOverview / Macro Regime Dashboard

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