Will Tonight's CPI Decide Next Week's Fed Rate Hike?

Original title: "Will Tonight's CPI Decide Next Week's Fed Rate Hike?"
Original source: Wall Street Insights

A difference of one decimal point could directly determine whether the Fed raises rates next week: a 0.2% month-over-month core CPI means holding steady, while 0.3% triggers a hike. Divisions within the Fed are clear, and bond markets, the dollar, the yen, and stocks are all on high alert. Goldman Sachs warns that if the data is moderate and the Fed chooses to hold steady, bond market concerns about a "policy mistake" will far outweigh the damage from hiking amid above-target inflation. Tonight's August CPI report will be one of the most market-sensitive inflation data releases in recent years. A difference of one decimal point is enough to decide whether the Fed initiates another rate hike in this cycle next week—and this gamble has already forced economists at top Wall Street institutions to be precise to the third decimal place.

Money markets currently price about a 70% probability of a 25 basis point rate hike at the September 16 FOMC meeting. Last week's strong nonfarm payrolls data and escalating geopolitical tensions in the Middle East have jointly pushed up hawkish expectations. Fed Governor Waller previously gave the clearest policy reaction function to date: if August inflation data shows the disinflation process continuing, he leans toward keeping rates unchanged; if the data runs hot, he would support a hike. Fed Chair Warsh stated at the Jackson Hole conference that unless inflation converges toward the 2% target fast enough, the policy job is not done.

Mainstream Wall Street forecasts cluster around a 0.2% month-over-month core CPI, but this is precisely the outcome most difficult for markets to price. According to JPMorgan's market intelligence team, 0.2% (rounded) means holding steady, while 0.3% means a hike. Bloomberg Chief US Economist Anna Wong said her team is calculating PCE inflation forecasts to the thousandth of a percent to gauge the policy implications of this "one of the most closely watched CPI reports in history." Tonight's data will directly reshape market pricing for the September, October, and even December rate paths.

Institutional forecasts: core CPI readings cluster near 0.2%

Major Wall Street institutions' forecasts for August core CPI are highly concentrated, but subtle differences are crucial.

JPMorgan forecasts August core CPI to rise 0.21% month-over-month, annualizing to about 2.37%, barely maintaining 2.4% after rounding. For core PCE, JPMorgan expects a 0.20% month-over-month increase and a 3.2% year-over-year rise. The bank also notes that 13 of the past 17 CPI releases have come in below expectations, and the current inflation surprise index is in the weakest 10% range of the past decade, so it maintains a below-consensus forecast and continues to hold short positions.

Bank of America Securities forecasts core CPI to rise 0.22% month-over-month and core PCE to rise 0.24%, annualizing to about 2.9%, with the year-over-year rate expected to climb to 3.4%. BofA economist Stephen Juneau believes this outcome is not enough to reassure the Fed about the inflation trend and is sufficient to support another rate hike at the September FOMC meeting.

Goldman Sachs forecasts core CPI to rise 0.22% month-over-month, translating to a 0.22% month-over-month increase in core PCE. Goldman specifically highlights three key components: used car prices are expected to rise 0.5%; owners' equivalent rent (OER) and rent components are expected to rise moderately by 0.22% and 0.23%, respectively; airfares are expected to jump 4.0%, reflecting continued pass-through of jet fuel costs.

Citi's forecast is more dovish, expecting core CPI to rise 0.18% month-over-month and core PCE to rise 0.19%, and believes this outcome would support the Fed holding steady in September.

Polymarket prediction markets show the median economist forecast at 2.4% year-over-year, and the market prices a significantly higher probability of a downside surprise (2.3% or lower) than an upside surprise (2.5% or higher).

Warsh and Waller: two signals, one game

Divisions within the Fed make interpreting this CPI data more complex.

Chair Warsh's Jackson Hole speech leaned hawkish, explicitly stating that unless core inflation converges clearly toward the 2% target at a sufficient pace, the Fed has more work to do. This wording was interpreted by markets as extremely low tolerance for inflation.

Waller's remarks were relatively moderate, providing a clear hedge. He said he is seeing signs of cooling inflation, with three-month core inflation improving significantly, and if August data continues the cooling trend, he supports holding steady in September.

His specific reference point: if the three-month annualized core inflation rate falls to 2.8%, "that is acceptable." But he also retained the stance of supporting a hike if the data runs hot. Waller also downplayed the inflationary pull of energy prices and tariffs, arguing that wage growth is consistent with the path back to target, and suggested that core PCE may not be the best measure of inflation trends, arguing that underlying inflation is actually "performing better" than core data suggests.

Goldman Sachs FICC co-head Anshul Sehgal described Warsh's and Waller's remarks as "two completely different interpretations," arguing that whether this cycle needs rate hikes remains undecided and depends largely on energy price trends and geopolitical developments. His view: rate hikes in this cycle are unlikely to exceed three times, and the 1-year forward rate pricing at 435 basis points implies about two and a half hikes, which "sounds roughly reasonable."

Bond and rates markets: 0.25% is the line between hiking and holding

Rates traders have focused on the precise decimal point of core CPI.

BofA rates strategist Meghan Swiber's scenario analysis shows: if core CPI rises 0.1% month-over-month, 2-year Treasury yields are expected to fall 10 to 5 basis points; if 0.2%, volatility is around ±5 basis points; if 0.3%, yields will rise 5 to 8 basis points. She specifically notes that a soft data surprise would trigger a larger rally than the selloff from a hot surprise—because rate hike expectations are already well priced and the market overall holds significant short positions.

Goldman Sachs macro trading desk's Brian Bingham points out that the Fed is in "the most contradictory situation," potentially deciding policy direction based on rounding in government data. He also worries that if the data is moderate and the Fed chooses to hold steady, bond market concerns about a "policy mistake" will far outweigh the damage from hiking amid above-target inflation.

BofA Securities historical data shows that 90% of Fed hawkish surprises occurred when the market had priced less than 3 basis points two days before the meeting, meaning if pricing is too high by then, the Fed actually not hiking could become a bigger surprise.

FX market: dollar at lows, data may intensify two-way volatility

The dollar enters this key report with weakness near four-month lows.

Goldman Sachs FX strategy head Mike Cahill believes that if the data runs hot (around 0.25% month-over-month) and is broad-based enough, the Fed will find it hard to avoid hiking, as it would breach the range set by Williams and Waller. If the data is soft (0.18% to 0.20%), the Fed can easily hold steady without triggering adverse market reactions. He attributes the dollar's recent weakness to three factors: the Fed's dovish tilt, the Treasury's policy preference for the exchange rate to play an adjustment role, and the independent strength of currencies like the yuan, yen, and won.

BofA FX strategist Alex Cohen notes that under the market consensus scenario (core CPI 0.2% month-over-month), the dollar will see two-way volatility, because whether to hike in September remains an open question. If the data is soft, the dollar's decline will be larger than its gain from hot data, with DXY losses estimated at a minimum of 0.5% to 0.75%, and October and December hike expectations will also recede sharply. If the data is hot, hike probability will approach 90%, and the dollar will initially rebound, but if the Fed subsequently fails to follow through, dollar credibility will erode further, and the dollar may instead weaken in tandem with long-end Treasuries.

On the yen, after USDJPY recently broke below the 155 area, Goldman Sachs G10 spot desk's Luke Molyneux believes that if the data meets expectations and supports holding steady, USDJPY is likely to extend its decline toward the 152.10 low area; if the data is hot, it may briefly rebound to the 157.50 to 158.00 range, but will still be viewed by the market as a shorting opportunity.

Stocks and risk assets: upside skew, but volatility to persist

In equities, JPMorgan's market strategy team believes the risk-reward is generally skewed to the upside.

If the data supports holding steady or a "hawkish hold," tech, momentum, and cyclical sectors are expected to be the main drivers of a rebound. JPMorgan positioning tracking data shows hedge funds have increased overall exposure for four consecutive trading days over the past week, with weekly net increases reaching the highest level since late June (+1.3 standard deviations), and releveraging room remains ample, constituting a potential upside catalyst.

But JPMorgan also notes that market moves will remain choppy before the data release, which is the direct reason the bank recently adjusted its short-term rating to "tactically neutral." Options markets currently imply about 1.0% single-day volatility for contracts expiring September 11.

The biggest tail risk is core inflation coming in significantly above expectations. If so, October and December hike expectations will be rapidly repriced, currently around 27% and 54% respectively, and will exert substantial pressure on equities.

The paradox of one number: precise to three decimal places

Another deeper implication of this report is an extreme stress test of "data-dependent" monetary policy itself.

Bloomberg Chief US Economist Anna Wong wrote that her team has been projecting core PCE forecasts to three decimal places to judge which way this rate decision leans. This was cited by FX trader Brent Donnelly, who contrasted it with Warsh's own earlier remarks—Warsh had criticized "data dependence" as having limited policy value in his 2025 speech, arguing that excessive focus on government data to two decimal places reflects "false precision and analytical laziness."

Yet as Donnelly pointed out, "we are now in that situation." Tonight's number may become the most delicate game between Fed policy credibility and market expectations.