Six weeks after the Federal Reserve raised interest rates, the dollar is up more than 1 percent as traders wait for signs of the central bank's next move.

The greenback swung between gains and losses Wednesday against most of its major peers as traders weighed whether the market turmoil that has greeted the start of 2016 will prompt U.S. policy makers to signal a slower pace of interest-rate increases.

Traders are jittery before central-bank meetings this week in the U.S., Japan, and New Zealand amid speculation that policy makers will be forced to address volatile markets. The greenback has rallied for the last two years on speculation that the Fed will boost borrowing costs in contrast to easing by its global peers.