Core CPI month-over-month, June 2026 (first print, SA)

Population stdev of core MoM over the last 24 months = 0.083pp — much tighter than headline (0.189). Using ~0.08-0.10pp as 1-sigma, the 80% band (z=1.28) is roughly point +/- ~0.11pp, i.e. about one rounding step either side.

Trailing-3 mean = +0.26%, trailing-6 mean = +0.25%. No trend; the series mean-reverts to roughly +0.25%. May's +0.2% is at the low end of the recent oscillation, so a small uptick toward +0.3% is as likely as a repeat +0.2%.

Base rate over the last 12 months: core MoM has averaged ~+0.25% and ranged 0.19-0.38%. The modal rounded outcome is +0.3% (months like Jan 0.30, Apr 0.38 round to 0.3-0.4; Feb/Mar/May round to 0.2). +0.3 and +0.2 split most of the probability.

Outside [0.1, 0.4] if: a sharp services re-acceleration (shelter, medical, insurance) or oil pass-through prints +0.5%; or an unusually soft month (goods deflation, OER softening) prints +0.0-0.1% and the lower bound is breached. Core's tight history makes both tails thin.

Mean-reversion to ~+0.25% plus a slight pass-through tilt -> point +0.3%. 80% CI = roughly +0.3 +/- one rounding step -> [0.1, 0.4] (asymmetric: capped near 0.4 by tight history, floor 0.1).

The control repeats the recent low-0.2 to low-0.3 percent core CPI range with one rounded step of uncertainty.

The component pack leaves the median at one rounded 0.3 percent print but adds a slightly higher upper tail for core goods and transport pass-through.

The resolver is the first official BLS CPI Summary release for the June 2026 reference month, using the seasonally adjusted CPI-U all items less food and energy monthly percent change, not later revised database values.

Base-rate/reference-class anchor: the five available 2026 core CPI monthly prints average 0.24 percent, with four of five at 0.2 percent and one at 0.4 percent. A one-decimal first print near 0.2 or 0.3 is therefore the central reference class.

Upside consideration: the large energy shock and transportation-cost pressure in spring 2026 could bleed into airfares, delivery-sensitive goods, and some services, making a 0.3 or 0.4 print plausible even if energy is excluded from core.

Counter-consideration: May showed clear offsets from vehicle insurance, household furnishings, and new vehicles, while shelter was only 0.3 percent; if those soft categories persist, another 0.2 print is very plausible.

Using the 2026 year-to-date core MoM average of (0.2+0.2+0.2+0.4+0.2)/5 = 0.24, I shift slightly upward for possible pass-through and rounding risk to a 0.3 percent point estimate; an 80 percent interval of 0.1 to 0.5 covers a soft repeat, typical noise, and an upside pass-through surprise.

The resolver is the BLS first print for CPI-U all items less food and energy, seasonally adjusted percent change from the preceding month, for reference month June 2026.

Base-rate step: the recent rounded BLS core monthly sequence for Jan-May 2026 is 0.3, 0.2, 0.2, 0.4, 0.2, with a mean of 0.26 and a median of 0.2; adding the FRED exact index changes keeps the center close to a rounded 0.2 to 0.3 print.

I center the forecast at 0.28 percent exact monthly growth, which rounds to a BLS-style 0.3 percent print. A practical 80 percent interval of 0.1 to 0.5 covers a downside soft-core month and an upside repeat of April-style firmness plus rounding risk.

Counter-consideration: the May release notes headline inflation was being lifted by energy, while the core row was only 0.2 percent; because energy is excluded from the resolver, the energy shock is not enough by itself to push core above 0.3, but second-round transportation or services effects keep upside risk in the interval.