A difference of a decimal point may directly decide whether the Federal Reserve raises interest rates next week: a core CPI of 0.2% month-on-month means holding steady, while 0.3% triggers a rate hike. There are clear divisions within the Fed, and the bond market, U.S. dollar, yen, and stock market are all on high alert. Goldman Sachs warns that if the data is moderate and the Fed chooses to stand pat, the bond market's concerns about a "policy mistake" will far outweigh the damage done by a rate hike in the event of inflation exceeding expectations.

Written by: Xu Chao, Wall Street Insights

The CPI report for August, released tonight, will be one of the most market-sensitive inflation data in recent years. A difference of a decimal point could determine whether the Federal Reserve initiates another rate hike in this cycle next week — and this betting game has forced top economists on Wall Street to sharpen their predictions to the third decimal place.

The money market currently prices in about a 70% probability that the FOMC meeting on September 16 will see a 25 basis point rate hike. Strong non-farm payroll data last week and rising geopolitical tensions in the Middle East have jointly raised hawkish expectations. Fed Governor Waller previously provided the clearest policy response function to date: if August's inflation data shows a continued process of disinflation, he tends to favor keeping rates unchanged; if the data is too hot, he would support a rate hike. Fed Chair Warsh indicated at the Jackson Hole conference that unless inflation converges towards the 2% target at a sufficiently fast pace, the policy work is not yet complete.

The mainstream forecasts on Wall Street are concentrated around a core CPI month-on-month increase of 0.2%, but this is precisely the outcome that is the hardest for the market to price. According to analysis from JPMorgan's market intelligence team, 0.2% (rounded) means holding steady, while 0.3% means a rate hike. Bloomberg's Chief U.S. Economist Anna Wong stated that her team is calculating the PCE inflation forecast with precision to the thousandth to assess the policy implications of what she calls "one of the most closely watched CPI reports in history". Tonight's data will directly reshape the market's pricing of interest rate paths for September, October, and even December.

Predictions from Various Institutions: Core CPI Focuses Around 0.2%

Major institutions on Wall Street have highly concentrated predictions for the August core CPI, but small differences are crucial.

According to JPMorgan's forecast, the month-on-month increase in August's core CPI is 0.21%, annualized to about 2.37%, barely maintaining at 2.4% after rounding. For core PCE, JPMorgan expects a month-on-month increase of 0.20%, year-on-year at 3.2%. The bank also noted that out of the last 17 CPI data releases, 13 were below expectations, and the current inflation surprise index is in the weakest 10% range of the past decade, hence they maintain a prediction below market consensus and continue to hold short positions.

BofA Securities predicts a month-on-month increase of 0.22% for core CPI and 0.24% for core PCE, annualized to about 2.9%, with year-on-year expected to rise to 3.4%. BofA economist Stephen Juneau believes this result is insufficient for the Fed to feel comfortable with the inflation trend, adequate to support another rate hike at the September FOMC meeting.

Goldman Sachs, on the other hand, predicts a month-on-month increase in core CPI of 0.22%, expecting this to translate into a rise of 0.22% for core PCE. Goldman specifically highlights three key components: used car prices are expected to rise by 0.5%; housing rents (OER) and rents are expected to rise modestly by 0.22% and 0.23%, respectively; and airline ticket prices are expected to surge by 4.0%, reflecting the continuous transmission of jet fuel costs.

Citi's forecast is more dovish, expecting core CPI to rise by 0.18%, core PCE by 0.19%, and believes this result will support the Fed's decision to stand pat in September.

Polymarket's market prediction shows that the median forecast among economists is a year-on-year increase of 2.4%, with significantly higher probabilities priced in for outcomes below expectations (2.3% and below) than for those exceeding expectations (2.5% and above).

Warsh and Waller: Two Signals, One Game

The divisions within the Federal Reserve make the interpretation of this CPI data more complex.

Chair Warsh's speech at Jackson Hole leaned hawkish, clearly stating that unless core inflation converges significantly towards the 2% target at a sufficient speed, the Fed still has more work to do. This wording has been interpreted by the market as having extremely low tolerance for inflation.

Waller's comments, on the other hand, are comparatively moderate, providing a clear hedge. He stated that he is seeing signs of disinflation, with a significant improvement in three-month core inflation, and if August's data continues to show cooling, it supports a hold in September.

The specific reference he gives is: if the annualized rate of three-month core inflation falls to 2.8%, "that is acceptable". But he also retains the position of supporting a rate hike if the data is too hot. Waller downplayed the inflationary impact of energy prices and tariffs, asserting that wage growth is consistent with the target path, and suggested that core PCE may not be the best metric for measuring inflation trends, believing that underlying inflation is actually "performing better" than the core data suggests.

Goldman Sachs' FICC co-head Anshul Sehgal described the positions of Warsh and Waller as "two completely different interpretations", asserting that whether this cycle requires a rate hike is still undecided and largely depends on the trajectory of energy prices and geopolitical developments. His view is that the number of rate hikes in this cycle is unlikely to exceed three, with the pricing of the 1-year forward rate at 435 basis points meaning about two and a half rate hikes, "which sounds roughly reasonable".

Bonds and Interest Rate Markets: 0.25% is the Threshold for a Rate Hike or a Hold

Interest rate traders have focused on the exact decimal of the core CPI.

BofA interest rate strategist Meghan Swiber's scenario analysis shows: if the core CPI is 0.1% month-on-month, the 2-year U.S. Treasury yield is expected to drop by 10 to 5 basis points; if it is 0.2%, volatility will be around ±5 basis points; if it is 0.3%, yields will rise by 5 to 8 basis points. She specifically noted that the increase triggered by weak data is likely to exceed the decline caused by strong data — because rate hike expectations have been sufficiently priced in and the market overall holds many short positions.

Goldman Sachs macro trading desk Brian Bingham pointed out that the Fed has found itself in the "most contradictory situation," potentially determining the policy direction due to the rounding of government data. He also expressed concern that if the data is moderate and the Fed chooses to hold, the bond market's fear of a "policy mistake" will far outweigh the damage done by a rate hike in the event of inflation exceeding expectations.

BofA Securities' historical data shows that 90% of the Fed's hawkish surprises occur within two days before a meeting when the market has priced within 3 basis points, which means that if prices are set too high by then, the Fed not hiking rates may become a greater surprise.

Forex Market: Dollar Weakness, Data May Intensify Two-Way Fluctuations

The dollar is entering this crucial report showing weakness near a nearly four-month low.

Goldman Sachs FX strategy head Mike Cahill believes that if the data is too hot (around 0.25% month-on-month) and broadly distributed enough, the Fed will find it hard to avoid a rate hike, as this would break the range defined by Williams and Waller. If the data is too weak (0.18% to 0.20%), the Fed can completely hold without causing adverse market reactions. He attributes the recent weakness of the dollar to three factors: the Fed's dovish tilt, the Treasury's policy preference for taking an adjustment role in exchange rates, and the strengthening independence of currencies like the yuan, yen, and won.

BofA FX strategist Alex Cohen pointed out that under the market consensus scenario (core CPI at 0.2%), the dollar's movements will exhibit two-way fluctuations, since whether a rate hike occurs in September will still be uncertain. If the data is weak, the dollar's drop will exceed the increase when the data is hot, with a minimum estimated decline in DXY of 0.5% to 0.75%, and expectations for rate hikes in October and December will also significantly recede. If the data is hot, the probability of a rate hike will approach 90%, leading to an initial rebound in the dollar, but if the Fed fails to follow up later, the deterioration of dollar credibility will deepen, and the dollar may actually weaken in conjunction with long-term U.S. Treasury bonds.

Regarding the yen, following the recent drop in USDJPY below the 155 range, Goldman Sachs G10 spot trading desk Luke Molyneux believes that if the data supports holding steady, USDJPY is likely to continue its downward trend, targeting the low near 152.10; if the data is hot, it may briefly rebound to the 157.50 to 158.00 range, but will still be viewed as a short opportunity by the market.

Stocks and Risk Assets: Upward Potential is Larger, but Volatility Will Persist

In the stock market, JPMorgan's market strategy team believes that the risk-return ratio is generally tilted upwards.

If the data supports holding steady or "hawks holding steady," technology, momentum, and cyclical sectors are expected to become the main drivers of a potential rebound. JPMorgan's positioning tracking data indicates that hedge funds have increased their overall exposure for four consecutive trading days in the past week, with a weekly net increase reaching the highest level since the end of June (+1.3 standard deviations), and additional leveraging space remains abundant, forming a potential upward catalyst.

However, JPMorgan also points out that market movements will still tend towards fluctuations before the data is released, which is the direct reason the bank recently adjusted its short-term rating to "tactical neutral." The options market currently implies about 1.0% one-day volatility for contracts expiring on September 11.

The greatest tail risk lies in core inflation significantly exceeding expectations. If that occurs, expectations for rate hikes in October and December will be rapidly repriced, currently about 27% and 54%, respectively, at that point, leading to substantial pressure on the stock market.

A Paradox of Numbers: Precise to Three Decimal Places

The report's deeper significance is an extreme stress test of the "data-dependent" monetary policy itself.

Bloomberg's Chief U.S. Economist Anna Wong wrote that her team is projecting core PCE forecasts with precision to the third decimal place to determine which side the rate hike decision is leaning towards. This was referenced by FX trader Brent Donnelly, creating an intriguing contrast with a prior remark from Warsh — in his 2025 speech, Warsh criticized the limited value of "data-dependent" policy, arguing that excessive focus on government data to two decimal places reflects "false precision and analytical laziness."

However, as Donnelly points out, "we are now in this situation." Tonight's figures may represent the most delicate game between the Federal Reserve's policy credibility and market expectations.