The Financial Times Stock Exchange 100 Index, also called the FTSE 100 Index, FTSE 100, FTSE, or, informally, the "Footsie", is the United Kingdom's best-known stock market index of the 100 most highly capitalised blue chip companies listed on the London Stock Exchange. Founded in 1984 by Stock Exchange to better reflect activity on the market, it replaced the Financial Times own FT 30. A new index afforded Stock Exchange the opportunity to launch the options contract derived from the FTSE's real-time data while competitors LIFFE launched the futures contract. With Margaret Thatcher's sweeping financial deregulation that culminated in the Big Bang the combination of a new index, LIFFE tradable derivatives and promotion by the Financial Times lead to the FTSE 100 becoming the most widely used barometer of whether the UK stock market was rising or falling. The index consists of 32 sectors, four of which have a market capitalisation exceeding £200 billion as at 3 May 2024. These are pharmaceuticals, oil & gas, metals and mining and banking services, which together account for approximately 47% of the index's market capitalisation. Wikipedia