Continuity of main contracts.
The main connection in futures means the continuity of the main contracts. In other words, the main connection contract is the mechanical connection of all the main contracts, forming a continuous contract of the contract with the largest daily trading volume and open interest. , which will form a relatively continuous K-line chart. That is the main contract.
The main contract is the connection of the main contracts in different periods. The index is formed by weighting all contracts according to the trading volume. Obviously, the main contract has gaps due to the change of months, and the index is the weight of all contracts, so there will be excellent continuity.