(Bloomberg) -- There is quiet yet mounting speculation in financial markets that China will need to take an extreme and highly controversial measure to support its moribund economy — devalue the yuan in a big-bang move. Most Read from BloombergMusk Makes Surprise China Visit in Search of Tesla Revenue BoostElliott Said to Have Built ‘Large’ Stake in Buffett-Favored SumitomoBlade to Offer Luxury Bus Service to Hamptons at Fare Up to $275Yen Watchers Ask When Japan Will Step In as Slide Accelerate