Analysts said the choppy trade in currencies and other markets -- stocks swung from losses to gains after Bernanke spoke while Treasuries fell -- reflected concern about the US economy and a realization that US interest rates will stay at record lows for years to come.

The euro was last up 0.8 percent at $1.4494, after reaching a New York session peak of $1.4501. It fell as low as $1.4327 after Bernanke spoke.

Copyright Reuters, 2011