Fed's Powell says US central bank will keep economy in 'good place' for as long as possible

Federal Reserve Chairman Jerome Powell voiced optimism about the state of the U.S. economy, but warned of long-term threats to the record-long expansion currently underway.

Those challenges include low growth, low inflation and low interest rates.

"Low can be good, but when inflation—and, consequently, interest rates—are too low, the Fed and other central banks have less room to cut rates to support the economy during downturns," Powell said on Friday during his opening remarks at the Fed Listens event in Washington, D.C.

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