66% After a 5.4% PPI: The August CPI Report of 11 September 2026 — Why the Fed Is Priced to Hike on the Inflation Gauge Friday Doesn't Publish

Thursday's Producer Price Index printed 0.4% on the month and 5.4% on the year, US crude closed above $100 for the first time since May, and fed funds futures moved to roughly a 66% chance of a quarter-point hike on 16 September. The August Consumer Price Index now lands at 8:30 a.m. Eastern on Friday 11 September, into a two-year note 13 basis points higher than it was on Wednesday. The report will almost certainly show core inflation at or near 2.5% — lower than it was in January, before this year's energy shock started. That is not the number the Committee targets. The Fed's mandate is written on the PCE price index, where core ran 3.3% in July, and the 0.8pp gap between the two gauges is the whole reason a Committee looking at 2.5% core CPI can still be a coin flip to tighten.

What lands, when, and into what

The BLS release schedule puts the August Consumer Price Index at 8:30 a.m. Eastern on Friday 11 September 2026. The next one, covering September, is 14 October — after the Committee has already decided. The Producer Price Index for August arrives at the same hour on Thursday 10 September, and the preliminary University of Michigan sentiment reading, which carries the household inflation-expectations series, follows at 10 a.m. Friday.

The Federal Open Market Committee meets on 15 and 16 September. Its communications blackout started on Saturday 5 September and runs through 17 September, which means these two releases will land into total official silence. Whatever the market makes of them, it makes alone.

The starting point is a Committee already split. At the 29 July meeting the FOMC held the target range at 3-1/2 to 3-3/4 percent by nine votes to three, with Presidents Hammack, Kashkari and Logan all preferring a quarter-point increase. The statement attributed above-target inflation to "supply shocks that have driven price increases in certain sectors, including energy." At Jackson Hole on 28 August, Chair Kevin Warsh told the symposium that while the summer's inflation readings "were better than expected," they "do not tell me that underlying trends have meaningfully improved," adding: "We must be confident that underlying inflation is moving to our objective, clearly and at sufficient speed. Otherwise, we have work to do." CNBC reported that the speech turned the September decision into a coin flip; as of 8 September, fed funds futures put a 25bp hike at roughly 56%.

Note the word Warsh used. Not inflation — underlying inflation. That is the core line, and it is the line this note is about.

The 2026 episode, in one table

Strip the year down to its two series and the shape is unmistakable.

Source: BLS Consumer Price Index, seasonally adjusted series, retrieved from the BLS public data API. The published unadjusted headline for July was 3.4%.

Headline inflation nearly doubled between February and May and has since retraced more than half of that. Core moved 0.35 of a percentage point across the same span and has given all of it back — July's 2.47% is below January's 2.51%, which is to say core inflation is now lower than it was before the shock began.

The driver is not subtle. In the twelve months to July the CPI energy index rose 14.73% and gasoline 24.64%. Within the month-to-month data, March alone put gasoline up 21.2% seasonally adjusted and utility piped gas up 18.8%. Those are supply-shock numbers, and they behave like supply-shock numbers: a violent level shift, then decay. June and July took energy down 5.71% and 1.48% respectively.

What Thursday's PPI actually printed

The Producer Price Index for final demand rose 0.4% in August, seasonally adjusted, exactly the Dow Jones consensus, and 5.4% over the twelve months, a tenth above the estimate. July was revised up to +0.1% from an original zero. The composition, as CNBC reported from the release, was almost entirely one story.

Source: BLS Producer Price Index, August 2026, released 10 September. Final demand index levels cross-checked against the BLS public data API.

Read the table twice. The first reading is the one the wires led with: wholesale inflation at 5.4% with the Fed's target at 2%. The second reading is the one that matters for Friday. Goods rose eleven times as fast as services, and within goods, energy did most of the work — the same shock, arriving one stage earlier in the pipeline. The core measure that strips food and energy out rose 0.2%, a tenth below what was expected. Producer inflation excluding the barrel did not accelerate in August.

That is the identical shape the Consumer Price Index has printed all year, one rung further up the supply chain: a violent energy line, a quiet core, and an annual rate that reads alarming because of the first and tells you very little about the second.

What the market did with it

The reaction was not to the core line. Within the session, fed funds futures moved from roughly 56% to about 66% priced for a quarter-point hike on 16 September, on the CME's FedWatch gauge — and PPI landed at the same hour that US crude pushed through $100 a barrel.

Sources: US Treasury daily par yield curve, 9 and 10 September 2026; CNBC market close. Both crude benchmarks recorded their highest close since 19 May; the S&P 500 fell for a fourth consecutive session.

Two things about that table are worth separating, because they are easy to merge into a single story and they are not the same mechanism. The move in the ten-year is an inflation-and-term-premium move: a higher oil price raises expected inflation across years, and the long end prices years. The move in the two-year is a policy move: it is the market saying the 16 September decision is more likely to be a hike than it thought on Wednesday morning. Only the second one is what carries into the dollar, and it is the leg to watch on Friday morning.

The awkward part for anyone reading this as a hawkish afternoon: the data that moved the odds was an energy-driven headline, and the FOMC's own July statement had already attributed above-target inflation to "supply shocks that have driven price increases in certain sectors, including energy." The Committee has told the market it is looking through exactly the line that just repriced the market's view of the Committee.

The number Friday doesn't publish

Here is the thing most previews of this release will skip. The Federal Reserve's 2% objective is not defined on the Consumer Price Index. It is defined on the Personal Consumption Expenditures price index, produced by the Bureau of Economic Analysis. And the two measures are currently telling different stories.

Sources: BLS Consumer Price Index, July 2026; BEA Personal Income and Outlays, July 2026, released 26 August.

That the Fed's own gauge sits above the widely quoted one is the reverse of the usual arrangement, and three structural differences explain it.

Weights. Shelter is roughly a third of the CPI basket and close to half of core CPI. In the PCE index, housing carries something nearer half that share. CPI shelter inflation was 3.16% in July and decelerating — so the single largest disinflationary force in the American price data does roughly twice as much work in the CPI as it does in the index the Fed targets. Nothing has to be wrong with either number for them to diverge on this alone.

Scope. The CPI measures what urban consumers pay out of pocket. The PCE measures consumption, including the very large share of health care paid on households' behalf by employers and government programmes. That spending is invisible to the CPI and material to the PCE.

Sources. For several service categories — hospital care and physician services most importantly — the BEA takes its prices from the Producer Price Index rather than the CPI. Thursday updated both. PPI for general medical and surgical hospitals rose 0.63% in August and now runs 3.68% over twelve months, up from 3.46% in July; offices of physicians was flat on the month at 1.21% annual, up from 1.11%. Portfolio management fees, another PPI line the BEA uses, fell 1.6% on the month but remain 18.8% higher than a year ago. Against those, the CPI's medical care services index ran 2.65% in July and its hospital services line 5.43%. Different surveys, different transaction definitions, different answers — and the ones that just firmed are the ones Friday will not report.

This is why Thursday was not a warm-up act. August PPI fed directly into the gauge the Committee will be looking at on Tuesday morning, through categories Friday's CPI does not measure at all — and on those categories it firmed, quietly, while the headline that moved the market was diesel. A market that trades Friday and ignores Thursday is trading the wrong release for the decision it cares about.

Gasoline is the part you can already compute

The headline number is the one the wires will lead with and the one that carries the least information, because most of it is already public.

The Energy Information Administration publishes a national average retail price for regular gasoline every week. Those weeks are already in.

Source: EIA Weekly Retail Gasoline and Diesel Prices, release of 1 September 2026.

August's average is 3.1% above July's before any seasonal adjustment. The comparison month is flat — the CPI's unadjusted gasoline index rose just 0.31% in August 2025 — so a move of that size lifts gasoline's annual rate from 24.64% to roughly 28%. And August's seasonal factor has added to the adjusted figure in each of the last three years: gasoline's seasonally adjusted monthly change exceeded its unadjusted change by 1.7 points in 2023, 1.5 in 2024 and 1.3 in 2025.

Put plainly: the energy contribution to Friday's headline was knowable a week ago. What is not knowable is the core line, and that is the only part of the release with information in it.

The base effect, and what each monthly print produces

Year-over-year rates are arithmetic, not judgement. August 2025 rose 0.287% on the headline index and 0.301% on core, unadjusted. Set those bases against July 2026's index levels and every possible monthly outcome maps to a known annual rate.

Calculated from BLS index levels: all items 333.918 in July 2026 against 323.976 in August 2025; core 337.133 against 329.970.

The Cleveland Fed's nowcast, updated 8 September, lands on 3.38% headline and 2.38% core — the +0.3% and +0.2% rows. It also carries a core PCE nowcast of 3.40% for the same month, which would leave the gap between the two core gauges essentially where it has been all summer.

Notice what the table says about the annual rate falling. For headline CPI to print below 3.1%, the month has to be flat outright — with pump prices up 3%. A headline near 3.4% therefore tells a policymaker very little they did not already know on 1 September.

Three scenarios, all read off the core line

The distribution that matters is narrow and it is on one number: core CPI, month over month, seasonally adjusted. July was +0.2%. The nowcast is +0.20%.

Core at +0.1% or below. Annual core drops towards 2.3% and the three-month annualised rate falls further below 2%. This is the print that hands the doves a clean argument, because it says the energy shock never became an inflation problem and is now visibly behind. Expect the front end to do the work: the two-year note, at 4.56% after Thursday, is the first thing that moves, and dollar carry moves with it. It is also the branch with the most room to move, because the two-year has just spent a session pricing in the opposite. Note the constraint, though — it does not resolve core PCE at 3.3%, and the test the Chair set was about underlying trends, not one month.

Core at +0.2%, in line. The likeliest single outcome, and the least useful. It confirms the trend without changing it, leaves annual core around 2.4-2.5%, and hands the decision back to the PCE-versus-CPI question and to a PPI report that has already firmed the PCE-only lines. In this branch the dollar's reaction is likely to be small and quickly retraced, because nothing in the policy path has been repriced. Positioning, another of the five factors, then matters more than the data does.

Core at +0.3% or above. The tail that would actually move things. It would break a three-month run of soft core readings, push the annualised quarterly rate back towards 2%, and give the three dissenters a contemporaneous number rather than an argument about what PCE implies. This is the branch in which the front end reprices hardest, because a hike would move from "priced at 66%" to simply priced — and two-thirds of the distance has already been travelled since Wednesday.

The asymmetry has narrowed since Thursday, and it is worth saying so. Before PPI, the market had absorbed two soft core CPI prints and no firm one, which made the upside surprise the larger repricing. Ten points of hike probability have since been taken out of that asymmetry. A firm core would still be the bigger move, but a soft one now has something to unwind.

What would change the picture

Thursday's PPI — answered, and in the direction that sharpens the problem. Not the headline, but the hospital, physician and portfolio-management lines that pass into core PCE without touching the CPI. Hospitals accelerated to 3.68% and physicians to 1.21%. If core CPI then runs soft on Friday, the two gauges diverge further, and the Committee walks into 15 September with its own target gauge firming while the number the public reads falls.

Shelter. The largest single weight in core CPI, at 3.16% and drifting lower. A stall here would stop the mechanical disinflation that has been flattering core CPI relative to core PCE all year — and would close the gap from the wrong end.

The nowcast revision. The Cleveland Fed updates its model every business day and PPI is one of its inputs, so the reading published after Thursday's release is the cleanest available read on Friday — and it is free.

Pump prices in September. The same weekly EIA series that made August's energy contribution predictable is already building October's. The Cleveland Fed's September nowcast sits at 0.40% headline against 0.19% core — another month in which the two lines say opposite things.

The dot plot. Whatever the CPI does on Friday, the 16 September projections carry more information about 2027 than any single print does about 2026. The August payroll beat of 162,000, covered here, removed the labour-market argument for waiting; the Jackson Hole framing, covered here, set the inflation test that Friday is supposed to answer. The euro side of the same energy shock, with the ECB deciding on 10 September, is set out in the ECB preview, and the fuller account of why the Fed's preferred gauge and the CPI keep diverging is in the PCE note.

For the currency itself the transmission is the interest-rate factor and nothing else: inflation does not lift a currency, a repriced policy path does. The factor-by-factor read on the dollar sits on the USD page, with the euro's on EUR and the yen's on JPY — the two crosses that have carried most of the dollar's 2026 range. What Pip Theory is and how it reads a release like this are set out on the about page.

Thursday was a rehearsal for that mistake. Producer prices rose 5.4% over the year, the market moved ten points of hike probability, and the core line underneath came in a tenth soft. A reader who finishes Friday morning knowing only the headline will know the least informative number in the document. The one to find is core, month over month, to one decimal place — and then to remember that it is an input to the Fed's target, not the target itself.

Educational macro context only — not investment advice.