Treasury Curve Flattens as Fed Hike Lifts Short-Term Yields

The gap between 2-year and 10-year Treasury yields narrowed after the Federal Reserve raised rates in September. By September 22, the 10-year yield was 4.96%, against 4.71% for the 2-year, a spread of 25 basis points.

The spread was 33 basis points on September 15, the day before the Fed’s decision. The central bank raised its benchmark rate by a quarter point, to a range of 3.75% to 4%, citing elevated inflation.

That shift makes the curve flatter: short-term borrowing costs have moved closer to long-term rates. The curve remained upward-sloping on September 22, so it had not inverted, when short-term yields exceed long-term ones.

Investors use the gap as one gauge of expectations for interest rates and economic growth. The 2-year yield is more sensitive to expected Fed moves, while the 10-year also reflects views on inflation, growth and the extra return investors demand to hold longer-term debt.

The flattening does not settle whether inflation will stay high or growth will cool. It shows that short-term rates rose more than long-term yields over the week after the Fed’s move, consistent with markets reassessing the path of policy.

The move matters beyond bond trading. Treasury yields help shape borrowing costs across the economy, including mortgage rates, while a smaller gap between short- and long-term rates can squeeze banks’ lending margins.

The next clues will come from inflation and labor-market data, alongside Fed signals about whether another increase is likely. If short-term yields keep catching up with longer-term ones, investors will have to judge whether the curve reflects persistent inflation or mounting concern about future growth.