PPI: Producer Price Index (PPI) is mainly used to measure the price changes of various commodities at different stages of production. It is usually used as an important indicator to observe the level of inflation as well as the consumer price index.

For the foreign exchange market, the market is more concerned about the monthly change of the final product PPI.

As food prices increase due to seasonal changes, and energy prices often fluctuate unexpectedly, in order to reflect the overall price changes of commodities more clearly, the change of food and energy prices is generally eliminated, thus forming the "core producer price index", and further observing the trend of inflation rate.