Some apparently believe there are no speed limits, and no utilization rate can be so elevated that it threatens higher inflation. The reality is that above-trend growth raises utilization rates and, after some point, excessively high utilization rates result in higher inflation.
But it is also true that threshold utilization rates and trend growth can change, that the current threshold levels for both utilization and growth rates are uncertain, that inflation can be affected by factors other than excess demand, and that policy is not infallible. Such uncertainty is a fact of life for both forecasters and policymakers.