WASHINGTON — The Federal Reserve announced a significant change today in how it manages interest rates by saying it plans to keep rates near zero even after inflation has exceeded the Fed’s 2% target level.

The change signifies that the Fed is prepared to tolerate a higher level of inflation than it generally has in the past. And it means that borrowing rates for households and businesses — for everything from auto loans and home mortgages to corporate expansion — will likely remain ultra-low for years to come.

The new goal says that “following periods when inflation has been running persistently below 2%, appropriate monetary policy will likely aim to achieve inflation moderately above 2% for some time.”

The new Fed policy sought to underscore its belief that a low jobless rate was good for the economy by saying it would seek to assess the “shortfalls” in employment from the maximum level.

In a speech detailing the changes, Chairman Jerome Powell made clear that the policy change reflects the reality that high inflation — once the biggest threat to the economy — no longer appears to pose a serious danger, even when unemployment is low and the economy is growing strongly. Rather, Powell said, the economy has evolved in a way that allows the Fed to keep rates much lower than it otherwise would without igniting price pressures.

“The economy is always evolving,” Powell said. “Our revised statement reflects our appreciation for the benefits of a strong labor market, particularly for many in low- and moderate-income communities and that a robust job market can be sustained without causing an unwelcome increase in inflation.”

In his speech, Powell said that the Fed’s decision to allow unemployment to fall to a 50-year low before the pandemic had played an important role in lifting the fortunes of low-income workers.