Since Federal Reserve Chairman Jay Powell made it clear last week that the central bank would be raising interest rates sooner than later, the pressing questions have been: How often? And by how much?

Banks and brokerage firms have been all over the place in their predictions, with some saying there’ll be three hikes for a total increase of less than 1%, all the way up to seven increases for a total of almost 2% — and likely even more in 2023.

Raising interest rates is often described as tapping the brakes on the economy. How many times the Fed has to do that depends on the central bank’s speedometer.

“The speedometer’s really measuring inflation,” said Kathy Bostjancic, chief U.S. economist at Oxford Economics.

She’s predicting the Fed will tap the brakes lightly this year four times because she thinks that the inflation needle is about to tick down.

“Maybe February, March, and then it gradually moderates through Q2 and really slows dramatically through the second half of the year,” she said.

If inflation doesn’t slow down and the speedometer starts creeping up, the Fed could tap the brakes and raise interest rates as many as seven times this year.

Under that scenario, “economic growth is probably still pretty good, where businesses are hiking wages aggressively in order to get workers and where inflation is still not yet under control,” said Guy LeBas, chief fixed-income strategist at Janney Montgomery Scott.

Thing is, it’s tough to find the sweet spot here.

“How do tap on the brakes just enough to slow down to the cruising speed you wanna achieve, when you really don’t know what that cruising speed exactly is in this environment?” said Kathy Jones, chief fixed-income strategist at Charles Schwab, a Marketplace underwriter.

Jones said the Fed could slam on the brakes and raise rates by more than expected — but that’s risky.

“It just makes it harder to finance activity, and that slows down the economy, and eventually that can lead to a recession,” Jones said.

The Fed is keeping its options open.

“And they’ve also been quite good about saying, ‘Look, this is all contingent on forecasts, and we may have a different economy to deal with in the future than we think we’re gonna have to deal with,'” said George Pearkes, macro strategist at Bespoke Investment Group. “So it could be that none of this is necessary. We just don’t know.”

How many times the Fed hikes interest rates will depend on what that inflation speedometer is reading every time the central bank’s leadership meets, Pearkes said.