中文：

CPI是消费者物价指数的缩写，它是一个重要的经济指标，用于衡量物价变化对消费者生活的影响。CPI通过计算一组代表性消费商品的平均价格水平，来反映物价变动的总体趋势。

CPI的计算方法是选择一组具有代表性的消费品，例如食品、衣物、住房等，然后计算这些商品的平均价格。这个平均价格被用作基准，与过去某个时点的平均价格进行比较，以计算出物价变动的百分比。

CPI是衡量通货膨胀的重要指标之一。如果CPI上升，说明物价上涨，通货膨胀压力加大，消费者的购买力下降。这可能会对消费者的生活水平和消费行为产生影响。因此，政府和央行通常会关注CPI的变化，以制定相应的经济政策来控制通货膨胀。

此外，CPI还可以用于评估保险公司的投资回报率。因为CPI是衡量通货膨胀的重要指标，如果保险公司的投资回报率低于CPI，那么投资者的实际收益可能会下降。

英文：

CPI is the abbreviation for Consumer Price Index, which is an important economic indicator used to measure the impact of price changes on consumers' lives. CPI calculates the average price level of a representative group of consumer goods to reflect the overall trend of price changes.

The calculation method of CPI is to select a representative group of consumer goods, such as food, clothing, housing, etc., and then calculate the average price of these goods. This average price is used as the benchmark, and compared with the average price at some previous time point to calculate the percentage change in prices.

CPI is an important indicator to measure inflation. If CPI rises, it means that prices are rising and inflationary pressure is increasing, which will reduce consumers' purchasing power. This may have an impact on consumers' living standards and consumption behavior. Therefore, governments and central banks usually pay attention to changes in CPI to formulate corresponding economic policies to control inflation.

In addition, CPI can also be used to evaluate insurance companies' investment return rates. Since CPI is an important indicator to measure inflation, if the investment return rate of insurance companies is lower than CPI, investors' actual returns may decline.