After recognizing this feature of the grain market, it is not difficult to understand the following phenomenon: when the grain output increases substantially, farmers can only compete to reduce prices to sell their own grain. However, due to the inflexibility of food demand, farmers can only sell food after drastically reducing food prices, which means that food prices often fall sharply at the time of grain harvest. If the percentage of falling food prices exceeds the percentage of increasing food production, there will be a situation in which the increase in food production will not increase or even decrease, that is, "cheap food will hurt farmers"
In the poor harvest year, due to the inflexibility of the demand curve, the reduction of the balanced quantity of agricultural products will be less than the increase of the balanced price caused by it, and finally the total income of farmers will increase.
Based on the above economic facts and experiences, many countries have successively implemented the policy of supporting prices for agricultural products in order to protect farmers and their interests and protect and support the development of agriculture. Its general practice is to reduce the impact of agricultural products by reducing the planting area of agricultural products, so as to maintain the price of agricultural products at a certain level and ensure the income of farmers and farmers.