Euronext NV’s venture market, known as Alternext, will launch the Alternext All-Share index on Sept. 4.

The new index will track the combined performance of all shares on the Alternext market, it will be weighted for market capitalization, and will be calculated daily. It will have a base level of 1,000, calculated back to the start of the year. So far this year, the index is up 18% from its starting point.

The makeup of the index will change with each new listing and delisting. Newly listed companies will be included two weeks after the date their shares begin trading.

When it debuts, the Alternext All-Share index will be made up of the 57 stocks currently traded on Alternext, of which 54 are listed in Paris and three in Brussels. They represent a total market capitalization of approximately €2.5 billion.

The firm says that the index is designed both as a tool for the management of portfolios specialized in small and mid-cap stocks and as a vehicle for the promotion of listed companies, helping them to reach a broader audience within the financial community.