Rates rise at weekly US Treasury auction to new 8-year highs

Interest rates on short-term Treasury bills inched higher in Monday's auction, posting another eight-year high.

The Treasury Department auctioned $39 billion in three-month bills at a discount rate of 0.905 percent, up from 0.900 percent last week, which had been the latest eight-year peak. Another $33 billion in six-month bills was auctioned at a discount rate of 1.020 percent, up from 1.015 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 $9,977.12, while a six-month bill sold for $9,948.43. That would equal an annualized rate of 0.920 percent for the three-month bills and 1.040 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 1.11 percent last Friday, little changed from 1.12 percent at the beginning of the week on May 8.