The Hang Seng increased 1380 points or 5.07% since the beginning of 2021, according to trading on a contract for difference (CFD) that tracks this benchmark index from Hong Kong. Historically, the Hong Kong Stock Market (HSI) reached an all time high of 33484.08 in January of 2018. The Hang Seng is a major stock market index which tracks the performance of around 50 largest companies listed in the Stock Exchange of Hong Kong. It is free floating, capitalization-weighted index. The Hang Seng has a base value of 100 as of June 30, 1964.