The 30-year Treasury yield closed at 5.47 percent on September 24, the highest since June 2004, as real yields rather than inflation expectations drove the selloff.

The Congressional Budget Office said federal debt held by the public would reach 222 percent of GDP in 2056 if interest rates run one percentage point above its baseline, against 175 percent in the baseline itself.

Treasury sold $70 billion of five-year notes at a 5.033% high yield on September 23, the highest since June 2006, with the weakest bid-to-cover since December 2018.

Treasury sold $69 billion of two-year notes at a 4.787% high yield on September 22, 2026, the highest since May 2024 and 79 basis points above the Fed's new target range.

The Fed raised the federal funds target range a quarter point to 3-3/4 to 4 percent, lifting the prime rate to 7.00 percent effective September 17, its first increase since July 2023.

Treasury's 20-year bond auction cleared at a record 5.420 percent with the weakest indirect share since February, and the 10-year closed at 5.00 percent.

Treasury sold 13-week bills at 3.970 percent and 26-week bills at 4.060 percent on September 14, a 17 basis point weekly jump, as the FOMC opened its two-day September meeting.

Federal debt fell to $40.048 trillion on September 10, down $127.9 billion from the August 31 record, as Treasury drew its cash balance at the Fed down by $205.4 billion.

The 2-year to 10-year Treasury spread narrowed to 33 basis points on September 11, its tightest since July 1, as the front end repriced before the September 15 and 16 FOMC meeting.

Core inflation cooled to 2.4 percent in August, the lowest since March 2021, but a 0.3 percent monthly gain pushed September Fed hike odds above 65 percent.