Interest rates on short-term Treasury bills rose in Monday's auction to their highest levels in more than eight years.
The Treasury Department auctioned $39 billion in three-month bills at a discount rate of 0.980 percent, up from 0.960 percent last week. Another $33 billion in six-month bills was auctioned at a discount rate of 1.070 percent, up from 1.060 percent last week.
The three-month rate was the highest since those bills averaged 1.250 percent on Oct. 20, 2008. The six-month rate was the highest since those bills averaged 1.100 percent on Nov. 3, 2008.
The discount rates reflect that the bills sell for less than face value. For a $10,000 bill, the three-month price was $9,975.23, while a six-month bill sold for $9,945.91. That would equal an annualized rate of 0.996 percent for the three-month bills and 1.091 percent for the six-month bills.
Separately, the Federal Reserve said Monday that the average yield for one-year Treasury bills, a popular index for making changes in adjustable rate mortgages, stood at 1.16 percent on Friday, unchanged from the level on May 30.