A New York Stock Exchange trader works on the floor on Dec. 17. Stocks rose nearly 300 points after the Federal Reserve announced it plans to begin raising interest rates next year. Andrew Burton/Getty Images hide caption

itoggle caption Andrew Burton/Getty Images

A notice in a store window in New York City announces a retail job opening. Now that unemployment has slipped below 6 percent, there's renewed interest in what the Federal Reserve's target for joblessness should be. Spencer Platt/Getty Images hide caption

itoggle caption Spencer Platt/Getty Images

Ben Bernanke is seen leaving his Washington, D.C., office on Jan. 31, his last day as chairman of the Federal Reserve. Saul Loeb/AFP/Getty Images hide caption

itoggle caption Saul Loeb/AFP/Getty Images

Janet Yellen during her confirmation hearing earlier this month. She's expected to win Senate approval to take over as head of the Federal Reserve. Brendan Smialowski /AFP/Getty Images hide caption

itoggle caption Brendan Smialowski /AFP/Getty Images

Janet Yellen, President Obama's nominee to become the next chairman of the Federal Reserve Board, is sworn in Thursday on Capitol Hill for her confirmation hearing. Jacquelyn Martin/AP hide caption

itoggle caption Jacquelyn Martin/AP