The price of pork is directly proportional to the price of corn. The change of pork price has an important influence on corn price. A large part of corn is used as feed, and corn is the largest energy feed in pig feed. Under normal circumstances, regardless of other factors, the prices of corn and pork should change in the same direction. If the price of pork rises and it is profitable to raise pigs, more people will raise pigs, thus promoting the increase of feed consumption demand, and the price of corn is likely to rise. On the contrary, if the price of pork falls, the profit of raising pigs will decrease, the number of pigs will decrease accordingly, the demand for feed will decrease, and the price of corn will probably fall.