The U.S. Treasury said it will at least double the size of liquidity-support buyback operations for longer-dated nominal coupon securities to at least $4 billion per operation from $2 billion, covering the 10- to 20-year and 20- to 30-year sectors from Sept. 9 through Nov. 4, 2026. The announcement pushed 30-year Treasury yields down by as much as nearly 10 basis points to about 5.187%, after they had hovered around their highest level in 19 years, and the bond was last trading roughly 7 basis points lower on the day. Analysts said the move shows Treasury is responding to stress in the long end of the market, where 5% or higher yields can raise borrowing costs for the government and private sector, weaken other asset classes and support the dollar. The buybacks are designed as a liquidity tool for off-the-run securities rather than a debt-reduction program, and earlier reporting in this topic record said the move also came just before a $16 billion auction of new 20-year bonds.