(Bloomberg) -- Japanese retail investors — who dominate spot trading in Tokyo’s foreign-exchange market — have increased bets on volatile currencies despite the rising risk of a monetary policy shift at home this year. Most Read from BloombergThe Bear Market Has Nearly Been Erased, Fewer Than 20 Months After It BeganPutin Warns Poland Over ‘Aggression’ Against Ally BelarusUS Recession Becomes Closer Call as Economists Rethink ForecastsWhy South Africa Is on the Brink of ChaosOil Trader Vitol Dou