The yen briefly strengthened to the low-158 range against the dollar in Tokyo on the 20th, gaining roughly 1 yen from the previous evening after the U.S. Treasury Department expanded its buyback program for long-term government bonds. The Treasury said on the 19th that it would raise the per-operation cap for Treasuries with more than 10 years remaining to maturity from $2 billion, or approximately ¥320 billion, to at least $4 billion. The program will run from September 9 through November 4 and target bonds with remaining maturities of 10–20 years and 20–30 years. The announcement pushed U.S. long-term yields lower across the board, narrowing the Japan-U.S. interest-rate differential and encouraging yen buying. The program is intended to improve liquidity by purchasing and retiring older, harder-to-trade Treasuries, while supporting demand and easing upward pressure on long-term interest rates. The yen is expected to remain sensitive to U.S. rate developments and differences between Japanese and U.S. monetary policy.