China’s yuan is on track to post one of its longest streaks of stable trading in a decade, just as its financial markets reel and growth sputters, reflecting how disconnected the currency remains from the country’s hefty challenges. 

Ten years ago Tuesday, the People’s Bank of China unpegged the yuan from the U.S. dollar.  Yet the currency remains tightly controlled, with the central bank regularly buying and selling it in the domestic foreign-exchange market to maintain a desired level. 

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