The Federal Reserve is widely expected to raise interest rates on Wednesday, and the Fed Chair, Janet Yellen, is set to hold her final press conference.

The dot plot, which shows where FOMC members think interest rates would be over the next few years, could increase by 12.5 basis points on average for 2018 and 2019, said Michael Gapen, the chief US economist at Barclays, in a note.

Though the Fed leadership is changing, Powell's appointment represents a continuation of the steady policy approach that Yellen has used in what's set to be one of the least volatile tenures.

But inflation has remained stubbornly low and below the Fed's 2% target, owing to what Yellen has at several times attributed to temporary factors including weak oil and cellphone-plan prices.

"Getting back to 2% inflation by the end of next year is not going to be too difficult as these one-time surprises come out," Peter Hooper, the chief economist at Deutsche Bank, said at a media briefing on Tuesday.