Dalian soybean contracts are divided into odd-numbered years and even-numbered years. After each contract expires and is delivered, trading will be suspended for half a year, and a new contract for the same month in odd (even)-numbered years will be listed.

The predecessor of Doudan a0909 is a0709. Trading was suspended for half a year after expiration in September 2007, so it was listed as a909 in March 2008.

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