TOKYO, Aug 20 (Reuters) - Yields on benchmark 10-year Japanese government bonds fell on Friday, as domestic shares slid to an eight month low and overnight declines on U.S. Treasury yields underpinned sentiment. The 10-year JGB yield fell 0.5 basis point to 0.005%, while benchmark 10-year JGB futures rose 0.04 point to 152.39, with a trading volume of 11,650 lots. Yields on notes with other maturities were unchanged. The 20-year JGB yield stayed at 0.400%, while the 30-year JGB yield remained at 0.645%. The two-year JGB yield was also flat at minus 0.145%, and the five-year yield was at minus 0.130%. The 40-year JGB yield was unchanged at 0.720%. Reporting by Tokyo markets team; editing by Philippa Fletcher Our Standards: The Thomson Reuters Trust Principles.