The Shenzhen Stock Exchange Component Index is a Capitalization Weighted Index. The constituents consist of the 500 top companies that issue A-shares on Shenzen Stock Exchange. The index was developed with a base value of 1000 as of July 20, 1994. Index trade volume on Q <GO> is scaled down by a factor of 1000. On May 20, 2015, number of members changed from 40 to 500.