Stock Index

An index tracks the combined performance of a defined basket of stocks.

A stock index measures the performance of a rules-based group of companies — the S&P 500 covers roughly the 500 largest US-listed companies, and the FTSE 100 covers the 100 largest on the London Stock Exchange. Most major indices are weighted by market capitalisation, so bigger companies move the index more.

Indices serve as market benchmarks and as the basis for index funds and ETFs. Membership changes periodically as companies grow, shrink, merge or delist.

Further Reading

AMAZON Common Stocks and Uncommon Profits

Philip Fisher's growth-investing classic on evaluating management and moats.

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AMAZON Stock Trading Journal

A structured logbook for tracking positions, theses and outcomes over time.

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AMAZON The Simple Path to Wealth

JL Collins' plain-English guide to index investing and financial independence.

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Recommended Reading & Tools

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AMAZON Rich Dad Poor Dad

Robert Kiyosaki's bestseller on assets, liabilities and financial literacy.

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