Shanghai and Zhengzhou directly ignore the calculated decimal, that is, give up. Dalian, on the other hand, directly carries the calculated decimal, that is, enters. Not rounding, but Shanghai, Zhengzhou and Dalian.
Your example above: The fuel comes from Shanghai. If you subtract the decimal 3378.59, it is 3378. Soybean comes from Dalian. If you round 3642.3, it is 3643.
The minimum change price of your example is 1. If the minimum change is not the variety of 1, the error will be greater. 654381October 7, take copper 08 12. The settlement price of 5 12 10 has dropped by 5% again, which is 512 10 * 95% = 48649.5, because the minimum changing price of copper is10.
When you look at the daily limit in Shanghai and Zhengzhou, the declines are both 5.0 1.6.02, which are slightly more, while the daily limit in Dalian is 4.98.4.99, which is similar. That's the truth.
Come back and add, I just said when it fell. It seems that all three exchanges were abandoned when they rose. Please check the previous data for details.