Big swings in the dollar made Thursday a blowout trading day in the $4 trillion-a-day foreign-exchange market. Citigroup , the world’s second-biggest foreign-exchange trading bank by market share, said it handled a record number of trades during that day, but declined to disclose the total Barclays , the third-largest, said it was the busiest day for trade in the dollar against the yen since 2008. The surge in volumes came after comments Wednesday by U.S. Federal Reserve Chairman Ben Bernanke and minutes from a recent Fed policy meeting suggested it might start pulling back on its bond purchases some time this year. ... (full story)