Supply and demand index is a qualitative index reflecting the economic trend of manufacturing industry. The calculation method is BCI= (number of rising varieties-number of falling varieties)/total. The smaller the index, the fiercer the competition. The smaller the value, the fiercer the competition among suppliers. So the bigger the supply and demand index, the better.

1. Count the number of rising varieties and falling varieties every month. The enterprise calculates by monitoring the monthly rise and fall of 100 basic raw materials which can best represent the eight major industries of the national economy.

2、BCI & gt； 0, reflecting the expansion of manufacturing economy; BCI=0, reflecting that the manufacturing economy is in a stable state; _CI:

1. Commodity supply and demand index is a commodity supply and demand index created by the business community, and it is a fixed-base index. The benchmark date is 201-12-01. This is the first commodity supply and demand index in China, and the business community hopes to make it an important evaluation index of manufacturing industry and a "barometer" of macroeconomic changes. Previously, a series of indices reflecting commodity prices were released, including the China Securities Index Company. Compared with other indexes, the latest commodity supply and demand index tracks the prices of eight industries in China, including energy, chemicals and textiles, covering a wider range. It is understood that the index of the business company is to monitor the price of the most upstream 100 basic raw materials in the national economy. According to the price comparison at the beginning and end of the month, the number of varieties that have risen and the number of varieties that have fallen in a month are counted, and then the BCI value is obtained by dividing the number of varieties that have risen by the total number.

Second, the characteristics of the supply and demand index:

1, the price fluctuates greatly. Only when commodity prices fluctuate greatly, traders who intend to avoid price risks need to use forward prices to determine prices first. For example, some commodities are subject to monopoly prices or planned prices, and the prices are basically unchanged. There is no need for commodity operators to use futures trading to avoid price risks or lock in costs.

Both supply and demand are great. The function of the futures market is based on the extensive participation of both the supply and demand sides of commodities. Only goods with large spot supply and demand can fully compete in a wide range and form authoritative prices.

3. Easy to classify and standardize. The quality standard of the delivered goods is stipulated in the futures contract in advance. Therefore, futures varieties must be commodities with stable quality, otherwise, it will be difficult to standardize.

4. It is convenient for storage and transportation. Commodity futures are generally long-term delivery commodities, which requires these commodities to be easy to store, not easy to deteriorate and convenient to transport, so as to ensure the smooth delivery of futures.