Treasury doubles long-bond buybacks, pushing 30-year yield down 9 bps

The Treasury Department moved to stabilize the bond market Wednesday by more than doubling the size of its buybacks for longer-dated government debt, a step that quickly drove yields lower. Treasury raised the maximum size of the operations from $2 billion to at least $4 billion and said it will focus on the 10- to 20-year and 20- to 30-year parts of the market. The expanded program starts Sept. 9 and runs through Nov. 4. After the move, the benchmark 10-year Treasury yield fell 5.7 basis points to 4.647%, while the 30-year yield dropped 9 basis points to 5.196%. The action comes after a sharp sell-off in long-term Treasurys and growing concern that higher yields could ripple through consumer borrowing, business financing and federal debt costs.