【中文版】

港股恒生指数是指香港恒生银行编制的股票价格指数，它涵盖了香港股市的主要蓝筹股和红筹股，是反映香港股市整体走势的重要指标。该指数的编制始于1969年，由恒生银行下属的恒生指数服务公司负责计算和发布。

恒生指数的编制遵循一定的原则和方法。它选取的股票样本通常为市值较大、交易活跃、财务状况良好的上市公司。这些股票通常涵盖了香港的主要行业，包括金融、地产、消费品等。在选取样本的过程中，恒生指数服务公司会定期进行审查和调整，以确保指数的代表性和公正性。

恒生指数的计算方法包括加权平均法和市值加权法。其中，加权平均法是指将所有股票的价格进行加权平均，得出一个平均价格指数；市值加权法则是指将股票的市值作为权重，加权平均所有股票的价格，得出一个市值加权价格指数。这两种方法都能较好地反映香港股市的整体走势。

恒生指数是投资者关注的重要指标之一，它反映了香港股市的整体表现和投资者的信心。该指数的波动与香港经济和政治环境的变化密切相关，因此被广泛用于宏观经济分析和投资决策。同时，恒生指数也是许多基金和投资产品的业绩比较基准之一，具有重要的参考价值。

【英文版】

The Hang Seng Index refers to the stock price index compiled by Hong Kong's Hang Seng Bank, which covers the main blue-chip and red-chip stocks in Hong Kong's stock market and is an important indicator reflecting the overall trend of Hong Kong's stock market. The index was first compiled in 1969 by Hang Seng Index Services, a subsidiary of Hang Seng Bank, and is calculated and released by Hang Seng Bank.

The Hang Seng Index is compiled in accordance with certain principles and methods. It typically selects listed companies with large market capitalization, active trading, and good financial conditions as sample stocks, covering major industries in Hong Kong including finance, real estate, consumer goods, etc. During the process of selecting samples, Hang Seng Index Services will conduct regular reviews and adjustments to ensure the representativeness and fairness of the index.

The calculation methods of the Hang Seng Index include weighted average method and market capitalization weighted method. The weighted average method refers to weighted average of all stock prices to obtain an average price index; the market capitalization weighted method refers to using the market capitalization of stocks as weights to weighted average the prices of all stocks to obtain a market capitalization weighted price index. These two methods can both reflect the overall trend of Hong Kong's stock market.

The Hang Seng Index is one of the important indicators investors pay attention to, reflecting the overall performance of Hong Kong's stock market and investors' confidence. The index's volatility is closely related to changes in Hong Kong's economic and political environment, so it is widely used for macroeconomic analysis and investment decision-making. At the same time, the Hang Seng Index is also one of the benchmarks for many funds and investment products, having important reference value.