The dollar extended its powerful rally, spurring central banks in developing countries to take steps to stabilize their own currencies and threatening to create headwinds for the long-running U.S. expansion.

The U.S. currency moved closer to parity with the euro after rising for the 10th straight day, the dollar’s longest winning streak against the euro since the European currency’s inception in 1999. The dollar also moved higher against the yen, which fell to its weakest levels against the U.S. currency since May 30.

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