我自己认为中国的货币要改革, different provinces have difference currency.and central bank independent.
even if until last century, like american, use flexible exchange rate for every single states.
according to optimal currency area theory, there are three rules to judge weather use single(fixed) exchange rate or flexible exchange rate.
1. regional disparity, if the regional disparity is high, it is better to use flexible exchange rate,
2.labour mobility, if labour mobility is high, use fixed exchange rate.
3. openness to trade, high trading, fixed exchange rate.
since inside china, there is significant economic divergence, advese shock will have different impact between region to region.
anyone agree with my point!!!!!!