Changes to the composition of an index

Indices reflect the development of a sector or a market. Their composition is therefore adjusted on a regular basis to account for current developments within the given frame of reference. For example, stocks may be incorporated into an index whose market capitalization and trading volume have increased, based on the number of shares in free float, which means that other companies will have to be removed. Exceptional events, such as a suspension of trading, debt composition proceedings, bankruptcy, and new listings also result in changes to the composition of an index.

Changes to the composition of the DAX® index are made only in September; changes to MDAX® and TecDAX® are also made in March. The composition of SDAX® can change on every review date, i.e. in March, June, September and December.

Moreover, a company can be taken out of an index outside the regularly scheduled chaining date if it no longer ranks among the top 45 companies in terms of market capitalisation or stock-exchange turnover. Respectively, a company can be included in an index if it becomes one of the 25 largest companies in terms of market capitalisation or stock-exchange turnover. A changeover within the index would take place as of the next chaining date.