Although the most recent readings on core inflation have been favorable, month-to-month movements in inflation are subject to considerable noise, and some of the recent improvement could also be the result of transitory influences.
The main reason for this may be the long history of research in an agreed paradigm using less than a handful of different approaches. For instance, as Governor Donald Kohn has pointed out last week, the basic framework for analysing inflation used by the Fed has remained fundamentally unchanged over the past 35 years.