The dollar declined from a four-year peak against the yen Friday after an unexpected fall in U.S. retail sales last month reinforced expectations the Federal Reserve will keep its monetary policy loose to support the U.S. economy.
But any rebound in the yen should be short-lived after the Bank of Japan unveiled aggressive monetary easing last week to fight decades-long deflation. Traders said it's only a matter of time before the dollar rises above the 100 yen mark.
U.S. retail sales fell 0.4 percent in March, the Commerce Department said, contracting for the second time in three months in a sign the American economy may have stumbled at the end of the first quarter.
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"It is the latest in a growing list of economic numbers that will likely keep the dollar pressured and the Fed in no hurry to normalize policy," said Omer Esiner, chief market analyst at Commonwealth Foreign Exchange in Washington.