According to sources cited by foreign media, the People's Bank of China has told some quote banks to adjust the counter-cyclical factor in the midpoint formula. Under the change, quote banks no longer filter the prior day's intraday volatility through that factor.
The other parameters of the formation mechanism were left unchanged, and no reason was given.
Removing the counter-cyclical filter may make the yuan fixing track market moves more closely, which could increase currency volatility. This affects the cost of dollar-priced imports for Chinese feed buyers, though the direct grain price effect is small.
After 991 past macro events, Chinese Yuan (CNY per USD) moved a median -0.0% over 5 sessions (49% higher; middle half -0.3% to +0.3%), and -0.1% over 20.
Moves of each commodity's benchmark from the last close before the event. Historical reads pool past events of the same kind; they describe what happened, not what will. Not investment advice.