This *2021* Waller speech makes for interesting reading today. At the time, Fed doves had been pointing to trimmed mean measures of inflation to argue against overreacting to spot inflation. Waller's point was that serially excluding 'one-off' outliers assumes no new one-offs take their place—a fallacy that, in hindsight, anticipated how the transitory framing failed. "The moral of this little example is that one needs to be careful when selectively ignoring data series—be it used car prices, food and energy prices, or household surveys of inflation expectations. All of these series convey important information about the evolution of inflation, and one should exhibit caution in dismissing data as outliers. We must keep our eyes open to inflationary pressures, wherever they come from, with consistency and rigor and stand ready to adjust policy if we conclude that such a change is warranted." https://www.federalreserve.gov/newsevents/speech/waller20211019a.htm