That's because other countries have lowered their rates to 0 and the U.S. is the only place to park money right now.
STFU MORON -
NEW YORK (Reuters) - U.S. Treasury debt yields fell on Wednesday, with 30-year yields setting all-time lows, as fears about a recession and trade tensions between China and the United States stoked unrelenting demand for low-risk government debt.
Inversion is spreading across the U.S. yield curve, where short-dated yields are running above long-dated ones, which has also unsettled investors as yield curve inversion often precedes a recession.