This image shows a digital screen displaying movements in the CAC 40 stock market index. The term "Cac 40" can be seen in blue letters, surrounded by graphs of stock market curves and figures, representing the fluctuations of the financial market. The whole image evokes the dynamic and complex world of the CAC 40 stock market.

The CAC 40 stock market, a leading stock market index on the Paris stock exchange, plays a significant role in the economy, attracting both seasoned investors and those with varied backgrounds. Centred around the thirty-nine cac 40 stocks and one, the cac 40 companies list inducts the most influential firms in France. This mirror of economic performance never ceases to raise questions and interest, providing invaluable information on the health of CAC 40 companies, their volatility, and the potential for capital gains offered by this stock market.

On the following pages, an exhaustive overview will be presented about the cac 40, first demystifying what the cac 40 is and why it stands out as an essential stock market index. This will be followed by a deep dive into the history and current composition of the CAC 40, focusing on understanding the foundations and evolution of this index. The workings of the CAC 40 will be examined, highlighting the mechanisms that govern the index and how it reflects the economy. Finally, the importance and economic impact of the CAC 40 will be discussed, before concluding with practical advice for those wishing to navigate the sometimes turbulent waters of CAC 40 investing.

What is the CAC 40?

The CAC 40, short for Cotation Assistée en Continu, is a major stock market index on the Paris Bourse. It is made up of 40 of the largest market capitalisations index of the top 100 French companies, based on the liquidity of their shares on Euronext. The index is weighted by floating market capitalisationThis method was adopted on 1 December 2003 to bring the CAC 40 into line with the standards of the major world indices.

The CAC 40 covers a wide range of business sectors, with companies regularly updated to maintain this representativeness. Euronext's Scientific Advisory Board, made up of independent experts, revises the index every three months or during major financial events, such as company mergers. This structure enables us to faithfully reflect the economic dynamics of France's major companies and to offer an overview of the overall economic health.

The history and composition of the CAC 40

Origin and creation of the index

The CAC 40, created with 1,000 basis points on 31 December 1987was inaugurated on 15 June 1988. It is the result of the transformation of the stock market system following the crash of October 1987, from management by stockbrokers to continuous assisted quotation. This change was formalised by Law 88-70 of 22 January 1988, marking a turning point in the management of stock market trading in France.

Index companies

The CAC 40 is composed of 40 stocks of French companiesselected from among the 100 companies with the highest trading volumes on Euronext. These companies are representative of various business sectors, ensuring a balanced representation of the country's economic dynamics.

Company inclusion criteria

A company's inclusion in the CAC 40 is determined by the Index Scientific Council, which mainly assesses the volume of transactions over the year and free float available on the market. This selection process ensures that even smaller companies can be represented, provided they meet the liquidity and capitalisation criteria.

How does the CAC 40 index work?

The CAC 40, an acronym for Cotation Assistée en Continu, is a stock market index that reflects the performance of the world's leading companies. 40 largest companies listed on the Paris stock exchange. The index is quoted continuously from Monday to Friday, from 9.00 am to 5.35 pmThe values are updated every 15 seconds.

Continuous quotation

The trading day begins with a pre-opening phase from 7.15am to 9.00am, during which orders accumulate but no transactions are made. Trading then begins from 9.00am to 5.35pm, allowing index values to fluctuate according to the number of transactions.

Index calculation method

The CAC 40 is calculated as weighted average by market capitalisation of its constituent stocks. The index is calculated on the basis of available-for-sale shares only, excluding those held on a stable basis by the founders or the State. In addition, no single security may exceed 15% of the total weighting of the index to avoid disproportionate influence by a single company.

Adjustments and revisions

The Index Scientific Committee, made up of independent experts, reviews the composition of the index every three months or when major financial events occur. This committee adjusts the weighting of companies according to their capitalisation and the liquidity of their securities. Companies may be added to or removed from the index according to these criteria, ensuring that the index remains representative of the French economy.

Importance and economic impact of the CAC 40

Economic indicators

The CAC 40, as the main Paris stock market index, plays a crucial role as an indicator of France's economic health. Changes in this index are often seen as a direct reflection of the performance of major French companies and, by extension, of the French and global economy.

Influence on financial markets

The CAC 40 has a significant influence on the financial markets, serving as a benchmark for many financial products. Instruments such as SICAVs, mutual funds and derivatives use the index as a performance barometer. The FCE, a futures contract on the CAC 40, illustrates how changes in the index can affect the values of derivatives.

Examples of historical fluctuations

Fluctuations in the CAC 40 have left their mark on recent economic history. In March 2020, for example, the index suffered a historic fall of 39 % due to the Covid-19 health crisisreflecting the global economic slowdown. However, the index has also shown its resilience, reaching all-time highs such as December 2023 when it peaked at 7,596 points. These examples demonstrate the impact of world events on the index and, consequently, on the global economy.

How do I invest in the CAC 40?

To invest in the CAC 40, several options are available. Investors can choose Index Invest services or derivatives such as ETFs, which replicate the index, or opt for index funds. It is crucial to select reliable management companies such as de Ravel Finance can be a good investment partner, or reputable issuers such as iShares or Amundi, based on performance, liquidity and service. However, index management may involve investing in underperforming companies.

Related financial income

Derivatives such as turbos, warrants, options and futures on the CAC 40 can be used for short-term investments, but they include high risks and require in-depth knowledge of their specific technical features. These instruments can also be used to shorten the index, offering opportunities in the event of a market downturn.

Risks and benefits

Investing in the CAC 40 via derivatives involves significant risk, especially if the products are leveraged. The potential gains must be weighed against the risk of capital loss, especially if the securities are sold before maturity.

Steps to investing

Choosing the right investment vehicle is essential. Options include life assurance, PEAs and securities accounts, each of which offers various tax advantages and levels of market access. For example, the PEA offers tax benefits after five years' holding, but does not allow investment in certain types of derivatives. Investors need to define their strategy, choose their investment vehicles and regularly monitor the performance of their investments to optimise returns.


Throughout this article, we have explored the various aspects of the CAC 40, from its definition, history and composition, to the way it operates and its significant economic impact on the financial markets. We have highlighted the importance of this stock market index as a barometer of the French economy and its key role for investors seeking to understand the nuances of the Paris stock market. Emphasis was also placed on CAC 40 investment strategies, highlighting the risks and opportunities that accompany such moves.

In short, the CAC 40 is an indispensable tool for anyone interested in stock market investment, offering both an overview of the vitality of the French economy and the prospects for capital gains. The information presented here will serve as a guide for investors, educating them on the importance of choosing their investment vehicles wisely while inviting them to keep abreast of market developments. The aim of this article was to demystify the CAC 40 and encourage a considered and informed approach to stock market investment.


  1. Which CAC 40 stocks have generated the best returns recently? The most profitable stocks in the CAC 40 in 2021 will come mainly from the banking sector, closely followed by the energy and telecoms sectors.
  2. How can we simply describe how the stock market works? The stock exchange is a market where various financial products, known as financial instruments or securities, are traded. A share is a security issued by a company seeking to raise finance. Owning a share therefore means holding a share in the capital of that company.
  3. Which CAC 40 stocks are currently recommended as buy candidates? This question requires updating or consulting a financial expert to obtain an accurate and up-to-date answer.
  4. How can we understand how the CAC 40 works? The CAC 40 is an index measured in points, based on an original value of 1,000 points established on 31 December 1987. For example, if the CAC 40 is at 4,000 points today, this means that an investment of €1,000 in 1987 in a product based on this index would be equivalent to €4,000 now.