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The Fed may have to get even more aggressive if its efforts to tighten aren't reflected in short-term rates, he said.
U.S. economic growth braked more sharply than initially thought in the fourth quarter, but the underlying fundamentals remained solid.
The Institute for Supply Management-Chicago Business Barometer fell far more than expected in February, plummeting to 45.8 from January's read of 59.4.
Harsh winter weather left U.S. consumers feeling a bit less confident this month, the University of Michigan said.
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