[3] CAC 40's base value of 1,000 was set on 31 December 1987, equivalent to a market capitalisation of 370,437,433,957.70 French francs.

[4] At each review date, the companies listed on Euronext Paris are ranked according to free float market capitalisation and share turnover over the prior 12 months.

[6] From the top 100 companies in this ranking, forty are chosen to enter the CAC 40 such that it is "a relevant benchmark for portfolio management" and "a suitable underlying asset for derivatives products".

The number of shares issued (used to calculate the market cap and hence the index weight) of a company is reviewed quarterly, on the third Friday of March, June, September and December.

A capping factor is used to limit the weights to 15% (if necessary), and is reviewed annually by the Index Steering Committee on the third Friday of September.

Although the CAC 40 is almost exclusively composed of French-domiciled companies, about 45% of its listed shares are owned by foreign investors, more than any other main European index.

[8] German, Japanese, American and British investors are amongst the most significant holders of CAC 40 shares.

This large percentage is due to the fact that CAC 40 companies are more international, or multinational, than any other European market.

[9] Source:[10] The following table shows the annual development of the CAC 40, which was calculated back to 1969.