"Futures" is the expectation of future spot prices. The futures market also has the function of price discovery, and it is always speculating on unknown prices. The spot market is generally clear about the price of the month, and there is no need for speculation in the futures market. In other words, the premium between spot and futures has tended to zero, so when the price difference between spot and futures is larger, that is, the premium is more unstable, futures will be valuable. In order to guide the spot market, the main contract is also the result of investors' general recognition of the market. For example, there are 10 people in this market, but 8 people think that the price of coking coal is the most active in September, so the trading volume is concentrated on the September contract, so the main contract becomes 1309. Correspondingly, the spot price in April became clear, and no one thought there was a natural April contract. So by the way, do you do futures? I shouldn't be a spot dealer, should I?