Why did the odds of an October 28 Fed rate hike drop from 50% to 38% in a single day?

Key Highlights

• The iShares 1-3 Year Treasury Bond ETF (NASDAQ:SHY) holds short-dated Treasuries that react to Fed expectations, and CME FedWatch showed the chance of an October 28 rate hike at 38%, down from 50% a day earlier.
• August Inflation rose less than expected, and price pressures in July were revised to a more moderate pace than first reported, which cut the case for an immediate additional hike.
• New York Fed President John Williams said on Tuesday he saw no urgency for further action, a signal that helped pull hike odds lower.
• Only days earlier, markets priced a 64% to 70% chance of a hike, so the swing shows how sensitive expectations are to each data point.

What Moved the Odds

The iShares 1-3 Year Treasury Bond ETF (NASDAQ:SHY) is sensitive to expectations for the Federal Reserve's policy rate, and those expectations changed fast. CME FedWatch showed a 38% chance of a quarter-point hike on October 28, versus 50% a day earlier. Two inputs drove the shift. First, August inflation rose less than economists expected, with the PCE index up 3.4% from a year earlier against 3.7% forecast. Second, Williams said he saw no urgency for more action. After the PCE report, some snapshots showed odds as low as 37%, so the exact figure depends on the time of day and the data provider.

How Fast the Mood Changed

A week earlier, the picture was very different. Money markets priced a hike at 64% to 70% after hawkish comments from several Fed officials and strong economic data, including a flash business-activity gauge that reached a five-year high. The Federal Reserve raised rates by a quarter point on September 16, so the debate is about whether one more increase is needed or whether the committee can pause and watch the data. The swing from roughly two-in-three to roughly one-in-three odds in days shows that markets are trading data, not a fixed path. The iShares 7-10 Year Treasury Bond ETF (NASDAQ:IEF) covers longer maturities that respond to the same signals.

What Could Reverse It

Odds can rebound quickly, and last week's swings prove it. Brent Crude rose more than 14% in September, and the 10-year Yield sits near 5.2%. A strong September jobs report on Friday, forecast at about 90,000 jobs, could revive hike bets, while a weak report would likely push them lower. ADP reported 90,000 private jobs on September 30, above the 70,000 expected. The Minneapolis Fed's Neel Kashkari has forecast one more hike this year, so the committee is not unanimous. The iShares 1-3 Year Treasury Bond ETF (NASDAQ:SHY) would likely respond first to any repricing.

Where Things Stand

The odds fell because softer inflation data and a no-urgency message from Williams outweighed the hawkish tone from earlier in the week. The iShares 1-3 Year Treasury Bond ETF (NASDAQ:SHY) reflects how fast markets can reprice the Fed path. A 38% chance still means a hike remains plausible, so the evidence is balanced rather than decisive, and any strong data point could reopen the debate. The next catalysts are Friday's jobs report, oil prices and the October 28 Fed decision.