US Federal Reserve chair Janet Yellen calmed investors on Monday, saying the bank's "extraordinary" commitment to boosting the economy will be needed for some time to come.
She hinted that interest rates will remain at near zero levels for an extended period.
At a conference in Chicago, she underlined that unemployment was still a big challenge for the economy and said that the Fed will maintain its extraordinary measures until the jobless rate falls a lot more.
''While there has been steady progress, there is also no doubt that the economy and the job market are not back to normal health," she said.
"The recovery still feels like a recession to many Americans, and it also looks that way in some economic statistics.
"In some ways, the job market is tougher now than in any recession. The numbers of people who have been trying to find work for more than six months or more than a year are much higher today than they ever were since records began decades ago."
