The CAC 40 is France's benchmark stock market index. It consists of 40 of the largest French stocks trading on Euronext Paris. Components are reviewed quarterly and weighted by free float market capitalization, with a cap of 15%. The index has been impacted by events like the dot-com bubble, subprime crisis, and Eurozone crisis. It is calculated every 15 seconds and tracks various industries like financials, communications, utilities and consumer goods.