Fed officials have grown steadily more aggressive in their battle against inflation this year, as the price burst sweeping the globe has proved more persistent than just about anyone expected. And there is little evidence, so far, that the Fed’s policy is working to tamp down price increases. If that continues, it could force Fed officials to do more next year to constrain rate increases. He said it was also possible that price increases would begin to fade, however, allowing for a pause. That happened after Mr. Powell’s July news conference, when the chair hinted that rate increases might soon slow and investors incorrectly began to expect an imminent central bank retreat.