The real estate price index is a relative number that dynamically describes the price changes of all kinds of real estate in a certain period, such as commerce, housing and industry, and the average trend and degree of overall price changes, including housing sales price index, housing rental price index, land transaction price index and property management price index.

The real estate price index is usually used to reflect the overall comprehensive change trend of real estate prices caused by social and economic phenomena that cannot be directly summarized. The real estate price index consists of market survey data. These data come from real estate in different places, and record the fluctuation track of market conditions at all times, forming a meteorological map of market conditions. Therefore, it is of great significance to quantitatively study, describe and predict the exponential trajectory. Because the real estate price index captures the core factor of market price, it has a direct and timely performance on the fluctuation of market conditions, thus becoming the main economic indicator to accurately and systematically describe the law of real estate price movement.

On the one hand, the real estate price index plays the role of a weather vane in the price mechanism, reflecting the range of price fluctuations, and using the price index to reflect the supply and demand situation of the market. The rise of price index indicates that supply and demand are tightening, while the decline of price index indicates that market supply and demand are slowing down; On the other hand, the real estate price index can be used to compare the development and characteristics of the real estate market in different regions. In the practical application of real estate price index, the real estate price index can not only reflect the overall changes of the real estate market in cities or regions, but also reflect the changes of different property types; The comparative analysis of the change track of real estate index and other commodity price indexes or GDP changes can not only reflect the cycle track of real estate market, but also provide important data for the study of macroeconomic cycle, and also be the basis of economic prosperity analysis and early warning research. Real estate price index is used to guide industry activities, and it is also an important reference to influence consumers' behavior and expectations.