“It’s perfectly conceivable it could take seven years” before rates are increased, given how difficult it’s been for the Fed to generate faster inflation, said former U.S. central bank official Roberto Perli, who is now a partner at Cornerstone Macro LLC.

In the last decade, it took more than three years for inflation-adjusted gross domestic product to rise back to the level that prevailed before the 2007-09 financial crisis. The recovery is expected to be faster this time: Deutsche Bank global head of economic research Peter Hooper sees GDP attaining its first-quarter level in the first half of 2022, though much will depend on the development and dissemination of a vaccine.

But staying the Fed’s hand will be a change in how it reacts to developments in the economy as a result of the framework review.

When it raised interest rates in December 2015, core inflation was clocked at 1.5% -- it’s since been revised lower -- while unemployment stood at 5%.

Economists said it’s hard to see the Fed increasing rates under similar conditions now.

The Fed first pronounced a 2% target for inflation in 2012, and officials took that to mean they would always shoot for 2%, no matter how much or for how long they missed. Bygones, they said, would be bygones. The trouble was that inflation has consistently run below their objective since then.

Under the new regime, the Fed is expected to seek an inflation rate that roughly averages 2% over time. So a modest rise in inflation above target would be welcomed, not feared, after an extended period where it undershot.

The Fed is also expected to codify a change in its approach toward achieving full employment. In the past, officials shied away from pushing joblessness below what was considered its long-run natural rate out of concern that would lead to too rapid inflation.

Now, the emphasis is on the benefits of a strong labor market for the economy and society. “They’re not going to act to cool off the labor market unless it’s generating unwanted inflation,” said Nomura Chief U.S. Economist Lewis Alexander. “That’s essentially walking away from the concept that there is a natural rate that it is irresponsible to push beyond.”

Powell has said he’d like to see the jobs market return to its pre-Covid-19 state, when unemployment stood at a half-century low of 3.5%. It’s now 10.2%.