TOKYO, May 21 (Reuters) - Yields on Japanese government bonds edged lower on Thursday, in line with U.S. Treasury yields as the U.S. government auctioned its first 20-year bond in decades.
Benchmark 10-year JGB futures rose 0.09 point to 152.36, with a trading volume of 10,396 lots, while the 10-year JGB yield fell 0.5 basis point to minus 0.005%.
The 20-year JGB yield and the 30-year JGB yield dropped 1.5 basis points each to 0.315% and 0.445%, respectively.
The 40-year JGB yield slipped 2.5 basis points to 0.455%.
At the short end of the curve, the two-year JGB yield fell 1 basis point to minus 0.180% while the five-year yield fell 0.5 basis point to minus 0.130%.
U.S. Treasury yields fell slightly on Wednesday as market players sought the safety of government debt after the launch of $20 billion of 20-year bond sale for the first time since 1986.
The Bank of Japan kept the size of its bond purchases unchanged on Thursday, buying 340 billion yen of 1-3 year JGBs and 350 billion yen of 3-5 year JGBs. (Reporting by Eimi Yamamitsu Editing by Robert Birsel)