The debate over how far to cut interest rates while inflation remains above target has pushed inflation measurement back to the center of monetary policy. What once seemed like a technical concern has become central to the policy debate, as policymakers, markets, and politicians argue over whether the data themselves justify easing—or whether easing is being justified by adjusting for known measurement lags.

That scrutiny has intensified amid heightened political pressure on the Federal Reserve, including public attacks on its leadership and ongoing scrutiny of its decisions, alongside inflation readings that have softened but remain above the Fed’s 2 percent goal. With another FOMC meeting approaching, small differences in the data now carry meaningful market and political consequences, and disputes increasingly turn on how inflation is measured rather than what policymakers are trying to achieve.

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