™An index uses a defined selection and weighting method; a 1% index rise does not imply every constituent rose 1%.
ETFs & Funds
Index
A rules-based measure designed to track a defined group of securities or market segment.
Plain-English context
Put the definition to work.
Identify constituents, weighting, currency and price versus total return; an index is not directly an investable fund.
Further reading and verification. Examples are hypothetical, not current quotes or recommendations. Product terms, tax treatment and market rules can change. Investor.gov — ETF bulletin