Federal Reserve Board Chair Janet Yellen listens to questions during a House Financial Services Committee hearing on Capitol Hill on Wednesday. Delivering the Federal Reserve's semiannual Monetary Policy Report to the House Committee, Yellen aired caution about global economic conditions. Mark Wilson/Getty Images hide caption

toggle caption Mark Wilson/Getty Images

Federal Reserve Bank Chair Janet Yellen holds a news conference after the central bank announced its first rate increase in more than 9 years. Chip Somodevilla/Getty Images hide caption

toggle caption Chip Somodevilla/Getty Images

Plummeting energy prices have hit the junk bond market hard, making investors worry that weaker oil and gas companies won't be able to pay back money they've borrowed. Above, a customer pumps gasoline in Pembroke, Mass. Stephan Savoia/AP hide caption

toggle caption Stephan Savoia/AP

April Thompson makes a purchase at Legacy Team Sales in Ocala, Fla., in September. Economists say October's surprisingly strong job growth will encourage the Federal Reserve to hike interest rates next month. So holiday shoppers may pay more for using credit cards. Doug Engle/Ocala Star-Banner/Landov hide caption

toggle caption Doug Engle/Ocala Star-Banner/Landov

NPR thanks our sponsors

Become an NPR sponsor