Fears of an economic slowdown sent investors fleeing to the safety of U.S. government bonds.
On Thursday, major retailers such as Costco and Macy's reported that April sales rose less that 1 percent, the worst performance since 2009 when the U.S. economy was coming out of a bad recession. Another report found that U.S. service companies, which employ roughly 90 percent of the work force, expanded their business more slowly in April.
The benchmark 10-year U.S. Treasury note rose 6.2 cents for every $100 invested. That pushed the note's yield down to 1.92 percent Thursday from 1.93 percent late Wednesday.
The price of the 30-year Treasury bond rose 15.2 cents for every $100 invested, pushing its yield down to 3.11 percent from 3.12 percent.
U.S. Treasurys are viewed as one of the safest investments in the world and usually rise in value when investors feel anxious.
The yield on the two-year Treasury note was unchanged at 0.27 percent.
The yield on the three-month Treasury bill fell to 0.08 percent, from 0.09 percent.