When Donald Trump moves the foreign-exchange market with 140 characters or less, currency traders ought to jump on for the ride.
That’s the conclusion of a Deutsche Bank AG examination of how the president’s comments on Twitter affect the value of the US dollar versus the yen, which is seen as the most responsive to potential changes in US policy because of its perceived safe-haven status. The president’s proclivity for tweeting -- and the ensuing jolts of volatility to largely plac ..
