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💸 CPI – September

MacroDrip

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Duality Research
Oct 24, 2025
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Today’s CPI report should be taken with a grain of salt, as it’s unlikely to be a “clean” reading given limited data access during the shutdown.


The inflation print for September just hit the tape, so let’s dive right in!

Here are the headline prints:

Year-over-Year:

✅ *US SEPTEMBER CPI RISES 3.0% Y/Y; EST. +3.1%
✅ *US SEPTEMBER CORE CPI RISES 3.0% Y/Y; EST. +3.1%

Month-over-Month:

✅ *US SEPTEMBER CPI RISES 0.3% M/M; EST. +0.4%
✅ *US SEPTEMBER CORE CPI RISES 0.2% M/M; EST. +0.3%

For a complete breakdown of last month’s CPI,
download our US Inflation Dashboard.

Get the Report

September CPI — Year-over-Year

Let’s start with our chart that shows the weight of the three main CPI categories and their respective sub-groups on the left. On the right, you can see how each item contributes to the overall index.
(see August CPI)


Next up, we’ve got two charts breaking down Core CPI — one showing year-over-year (YoY) changes and the other highlighting month-over-month (MoM) shifts, focusing on items with the most disproportionate impact.

September Core CPI — Year-over-Year

(see August Core CPI YoY)

September Core CPI — Month-over-Month

(see August Core CPI MoM)


Overall, a soft CPI print for September.

Core CPI was up 0.23% on the month, with some outsized drivers like Lodging, and especially Airline Fares.

Notably, some items saw significant declines this time, particularly Professional Medical Services, Car Insurance, and Used Cars.

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