CPI Y/Y
Actual: 4.0%
Previous: 3.5% (July)
Sharp acceleration, published the day after the already-analyzed RBA hike
CPI M/M
Actual: 0.4% (original), 0.7% (seasonally adjusted)
High seasonally adjusted monthly pace, consistent with a clear acceleration
Trimmed mean Y/Y
Actual: 3.6%
Previous: 3.6%, unchanged
Stability sharply contrasting with the headline jump
The real signal, exactly the pattern the RBA just validated
This print confirms point by point the prior day's RBA statement, which cited "upside risks materialising" and "recent inflation outcomes stronger than expected"
The stable trimmed mean while the headline surges reproduces exactly the pattern already documented in this series' July CPI, confirming the shock stays concentrated in specific categories rather than broad-based across the economy
Transport, the real engine
Actual: 5.6% y/y (versus 4.6% in July)
On the month: +4.2% original, +4.3% seasonally adjusted, by far the sharpest monthly move of any group
Directly tracks the broadening Middle East conflict and rising energy prices explicitly cited in the prior day's RBA statement
Housing, second contributor
Actual: 5.7% y/y, unchanged from the prior month
The largest weighted contributor to the index, consistent with falling house prices but rising construction/rental costs already documented in the RBA statement
Disinflationary signal, discretionary vs non-discretionary
Discretionary spending y/y: 3.0%, on the month: -0.2%
Non-discretionary spending y/y: 4.7%, on the month: +0.9%
A sharp gap confirming the RBA's read on discretionary consumption easing while constrained categories (energy, housing) keep weighing
Goods vs services, the real divergence
Goods y/y: 4.2%, on the month: +1.0%
Services y/y: 3.7%, on the month: -0.2%
Goods accelerating clearly faster than services, consistent with an external supply shock (energy, imports) rather than domestic services demand overheating
Tradables vs non-tradables
Tradables y/y: 2.9%, on the month: +1.3%
Non-tradables y/y: 4.5%, on the month: 0.0%
Tradables (exposed to international trade, fuel included) accelerating sharply on the month, further confirming the shock's external origin
Regional divergence
Adelaide (4.7%) and Hobart (4.8%) leading, consistent with prior Australia releases in this series
Melbourne the most moderate at 3.5%
Adelaide housing: 7.9% y/y, a considerable gap versus Melbourne (4.5%)
Food, disinflation continuing
Actual: 3.0% y/y, unchanged, the only major group down on the month (-0.1%)
Confirms the trend already noted in this series' July CPI (smallest contribution since 2021)
Implications
AUD: this print retroactively validates the prior day's RBA hike and reinforces the tightening cycle's credibility, consistent with the already-documented 2027 cumulative (65bp) and the 99% odds that were confirmed
Trimmed mean stability could however limit the scale of any additional bullish reaction, the market having already largely priced the event ahead of the release
AUD/USD: this CPI, combined with the already-delivered RBA hike, sustains a structural bullish bias for AUD, to be weighed against the oil/USD dynamic that remains the dominant factor identified this week
AUD/NZD: the conviction gap between the RBA (99% ahead of the meeting, now confirmed) and RBNZ (81%) could keep favoring AUD if this print encourages the RBA to maintain a firm tone going forward
Point of caution
The pullback in discretionary spending (-0.2% on the month) is the most important signal to watch in coming months, the RBA must keep tightening without choking already-fragile consumption
The goods/services and tradables/non-tradables divergence confirms this shock remains, for now, external and concentrated rather than a sign of broad domestic inflation that would require much more aggressive tightening