09 is a futures contract due in September.

03 stands for the futures contract that will expire on March 20th13rd next year. 09 is the contract that expired on September 20th, 200912. The principle is to use the latest time. All contracts after 2007 are from this year, and all contracts before 2007 are from next year.

09 12 holds a high position because these two months are the months of quarterly settlement, and many companies have major transactions in these months, so the turnover in these months has been relatively large. As for 07 and 08, they are about to expire, and there have been many changes before, so the positions are relatively large.

This phenomenon has always been like this, and there is nothing special about it.

If the warehouse moves, it usually moves every month.