At present, the global import and export trade of bulk commodities is mostly based on the spot pricing of major global futures markets, that is, spot price = futures price+basis price. Basis is the difference between spot price and futures price at a specific time and place, which is mainly affected by transportation cost. Generally speaking, the basis difference near the sales area is mostly positive, while the basis difference near the production area is often negative. Of course, changes in market supply and demand and people's price expectations will also lead to changes in basis. When the market supply exceeds demand, the base price tends to narrow; On the contrary, when the market is in short supply, the basis will be strengthened. In the United States, because the quotation of agricultural futures trading is based on the basis of a certain month's futures contract, the basis change has obvious seasonality. Generally, in the harvest season of crops in the United States and South America, the basis is at the lowest level, and gradually rises after one or two months. From a historical point of view, the trading mode and pricing mechanism of international bulk agricultural products have experienced the development process from spot trading-forward spot trading-exchange futures trading-OTC futures trading (various forms of derivatives). Grain trade originated in America. /kloc-At the beginning of the 9th century, in order to solve the problem of timely buying and selling of grain and avoid the risk of price fluctuation, commodity trading began in the form of forward contracts between farmers in the west and processors in the east. With the continuous concentration of grain trading and the development of forward trading, Chicago Board of Trade (CBOT) was founded by 82 grain traders on 1848. 1865, CBOT replaced forward contracts with standard futures contracts, and implemented the margin system, and floor trading began to develop. In 1970s, OTC derivatives market transactions also appeared, and options, swaps and other contract forms appeared. After a long-term evolution, international bulk agricultural products trading has formed an international trading system and an international market system with futures trading as the mainstay and multiple trading methods coexisting. Because the futures market price can reflect the world's expectation of the price of bulk agricultural products and the real relationship between market supply and demand, with the establishment of the international trade and market system of agricultural products mainly based on futures trading, the futures market has gradually become the center of the benchmark price of international agricultural products.

American futures market price is the weather vane of global agricultural product price.

As the United States is the largest exporter of agricultural products in the world, its agricultural futures trading has a long history. The futures market price in the United States is not only the basis for setting the price of agricultural products in the United States, but also provides a price reference standard for agricultural products markets around the world. For example, CBOT's futures prices of corn, soybeans, wheat and other varieties are not only an important reference for spot prices in the United States, but also dominate the formation of global prices of major agricultural products such as cereals and soybeans with its market influence; The cotton futures price of New York Futures Exchange is not only the basis for the pricing of American cotton industry, but also an important guide for the global cotton trade price.

Taking soybeans as an example, this paper explains the formation process of futures prices of CBOT bulk agricultural products. In CBOT, soybean futures trading is an organic system involving many trading subjects such as circulation, trade, processing enterprises and farmers. The price formation process is as follows: USDA releases the annual yield forecast and actual statistical data of major soybean producing areas in the United States, and CBOT futures traders mainly buy and sell futures based on USDA soybean yield information to form the futures market price of soybeans; Farmers determine the production arrangement for the next year according to the supply and demand trend of futures prices, so as to reduce blindness and risk in production. Traders determine the price in the spot trade contract through the futures price of agricultural products to avoid the risk of price fluctuation.

Obviously, domestic soybean production in the United States is the dominant factor of CBOT soybean futures price fluctuation. This futures pricing mechanism based on domestic soybean production in the United States is very conducive to protecting the interests of American soybean producers and operators. In recent years, although the soybean production in South American countries has increased rapidly, multinational companies led by the United States have monopolized the international soybean trade by centrally controlling the soybean circulation channels in these countries. Therefore, the changes in the world soybean production pattern have not changed the pricing mechanism in which the US futures market dominates the world agricultural products market.

Three factors affecting the pricing mechanism of international agricultural products.

As the core of the pricing mechanism of international bulk agricultural products is the futures price of CBOT agricultural products, the factors affecting the futures price of CBOT agricultural products have also become important factors affecting the pricing mechanism of international bulk agricultural products, mainly in the following aspects:

First, the relationship between supply and demand is the basis of pricing international bulk agricultural products. The change of commodity prices is determined by the relationship between market supply and demand, which is the most basic economic principle. Under the influence of supply and demand, commodity prices will automatically fluctuate around value. Other things being equal, if the supply of a commodity increases, the price of the commodity will fall, and vice versa; When the demand for a commodity increases, its price will rise, and vice versa. It is precisely because of this dynamic balance between supply and demand that the market price of commodities is formed. Although the factors affecting price changes may be varied in form, in the final analysis, the relationship between supply and demand has changed.

Second, the trend of the US dollar exchange rate is another important factor that affects the pricing of international agricultural products. Global bulk agricultural products are usually denominated in US dollars, and the change of US dollar exchange rate directly affects the trend of spot prices and futures prices of bulk agricultural products. When the dollar depreciates, the futures price of CBOT agricultural products will rise; When the dollar appreciates, the futures price of CBOT bulk agricultural products will fall.

Third, the international organization of agricultural products market influences the international pricing power to a great extent. Under the premise of perfect competition, information symmetry and zero transaction cost, the market price of bulk agricultural products is completely determined by the supply and demand relationship of the commodity. However, in real life, the international market of bulk agricultural products is not a completely competitive market, and the degree of market organization is an important factor affecting the pricing of international agricultural products. Judging from the current situation, multinational companies from a few developed countries dominate the pricing power of the international agricultural products market. At present, 80% of the world's grain trade volume is controlled by four multinational grain merchants "ABCD" with a history of 100 years, namely ADM of the United States, Bunge of the United States, Cargill of the United States and LouisDreyfus of France. These four multinational grain merchants are often called "behind the scenes" in the international grain market. With the advantages of capital and experience, these international giants have achieved absolute control over upstream raw materials, futures, midstream production and processing, brands and downstream market channels and sources, and are important participants and deciders in the pricing of international bulk agricultural products.

In addition, there are some non-main factors that are also affecting the trend of international agricultural product transaction prices. These non-major factors mainly include fund positions, weather factors, agricultural subsidies and reports issued by the United States Department of Agriculture (USDA). In essence, the influence of these non-main factors on the pricing of bulk agricultural products is still through the relationship between supply and demand. When the main factors determine the periodic trend of the prices of bulk agricultural products, other factors will become catalysts for the price trend and accelerate the rise and fall of the international prices of bulk agricultural products; In some cases, these non-major factors will also be transformed into major factors and play a key role.

Taking American agricultural subsidies as an example to see its influence on the pricing mechanism of international bulk agricultural products. The U.S. government has provided a lot of economic assistance and subsidies for domestic agricultural production. According to the report released by OECD, in 2002, the agricultural subsidies in the United States reached 39.56 billion US dollars, accounting for 16.84% of the total subsidies in developed countries and 18% of their agricultural income. American agricultural subsidies have an important impact on the pricing mechanism of international bulk agricultural products. First of all, the change of American government subsidies to different crops will directly affect the planting area and output of this crop, and then affect the futures price of CBOT agricultural products. For example, in May 2002, the US government passed the Agricultural Products Subsidy Act (referred to as the "New Agricultural Law"), the core content of which was to increase subsidies to agriculture, but the price of soybean loans from 2002 to 2007 was lowered from $526/bushel before 2002 to 500 yuan/bushel. The reduction of soybean subsidies has reduced the enthusiasm of farmers to grow soybeans to some extent. In 2003, the soybean planting area in the United States decreased by 7%, which led to the imbalance between soybean supply and demand in the world. Due to insufficient supply, the price of CBOT soybean rose rapidly in the second half of 2003. On the other hand, huge agricultural subsidies distort the pricing mechanism of international bulk agricultural products. Subsidies are a means to gain price competitive advantage, and the huge agricultural subsidies in the United States have greatly distorted the pricing basis of international agricultural products.