The Hang Seng is the leading index for shares traded on the Hong Kong Stock Exchange. Started in 1969, the index consists of the 33 largest companies that trade on the exchange. The index is maintained by a subsidiary of Hang Seng Bank. It is a capitalization-weighted index, meaning that the largest firms (based on market value) carry the greatest weight in the Hang Seng. The index represents approximately 70% of the value of all stocks traded on the Hong Kong Stock Exchange. The index can be further divided into four sub-indices: Commerce, Finance, Property and Utilities.

Additional Information:
Hang Seng Website