Two of the top bourses in China said they will launch a new stock index later this month that covers 500 companies listed in the mainland, Hong Kong and Taiwan, giving investors greater access to these still-buoyant markets.

China Securities Index Co, set up by bourses in Shanghai and Shenzhen, will start to publish the CSI Cross-Straits 500 Index on 18 January, according to a statement on the firm’s website.

The base date of the index is 31 December, 2004, and the base value is 1000. The respective Yuan-denominated, HK Dollar-denominated, TWD-denominated and US Dollar-denominated price indices as well as the relevant total return index are to be launched at the same time, the statement said.

Out of the total of 500 index constituents, 300 are from CSI 300 Index, 100 are from CSI HK 100 Index, 100 are largest 100 securities by market-cap in Taiwan market. In principle, the constituents are semi-annually reviewed and adjusted. The adjustment ratio normally does not exceed 10 per cent.