Recent September core CPI data surprised to the upside at +0.3% month-over-month against consensus expectations for +0.2%, lifting the year-over-year rate to 2.6% and underscoring pass-through from elevated energy prices amid geopolitical tensions. This outcome has kept trader-implied odds tightly clustered between a 0.2% and 0.3% October print, reflecting uncertainty over whether shelter costs, supercore services, and goods prices will sustain momentum or moderate as base effects from prior energy spikes ease. Markets price in roughly equal probability for these two outcomes, with lower readings viewed as contingent on continued cooling in core services ex-shelter while upside risks stem from persistent inflation in housing and select goods categories ahead of the mid-November release.