【中文版】

账面回报倍数是一种用于评估投资回报的财务指标，通常用于衡量投资组合或特定证券的投资表现。它表示投资组合或证券的收益与投资本金的比值，通常用于比较不同投资组合或证券的收益表现。

账面回报倍数的计算公式为：账面回报倍数 = （期末价值 - 期初价值）/ 期初价值。其中，期末价值表示投资组合或证券在投资期末的价值，而期初价值则表示投资组合或证券在投资期初的价值。

例如，假设某个投资者在年初投资了100万元，到年底时该投资组合的价值为150万元，则该投资组合的账面回报倍数为（150万 - 100万）/ 100万 = 0.5倍。这意味着该投资组合的投资回报率为50%。

账面回报倍数是一个重要的财务指标，可以帮助投资者评估他们的投资组合或证券的投资表现，并比较不同投资组合或证券的收益表现。然而，需要注意的是，账面回报倍数只是衡量投资表现的指标之一，投资者在做出投资决策时还应考虑其他因素，如风险、资产配置等。

【英文版】

Book return multiple is a financial metric used to evaluate investment returns, typically used to measure the investment performance of a portfolio or a specific security. It represents the ratio of the return on investment to the amount invested, and is commonly used to compare the performance of different portfolios or securities.

The formula for calculating book return multiple is: book return multiple = (ending value - beginning value) / beginning value. The ending value refers to the value of the investment portfolio or security at the end of the investment period, while the beginning value refers to the value at the beginning of the investment period.

For example, if an investor invests 1 million yuan at the beginning of the year and the value of the investment portfolio is 1.5 million yuan at the end of the year, then the book return multiple of the investment portfolio is (1.5 million - 1 million) / 1 million = 0.5 times. This means that the investment return rate of the investment portfolio is 50%.

Book return multiple is an important financial metric that helps investors evaluate the performance of their investment portfolios or securities, and compare the performance of different portfolios or securities. However, it should be noted that book return multiple is only one of the metrics used to measure investment performance, and investors should consider other factors such as risk and asset allocation when making investment decisions.