Rates rise at US Treasury auction to highest since fall 2008

Interest rates on short-term Treasury bills rose in Monday's auction to their highest levels since October 2008.

The Treasury Department auctioned $39 billion in three-month bills at a discount rate of 1.01 percent, up from 0.99 percent last week. Another $33 billion in six-month bills was auctioned at a discount rate of 1.12 percent, up from 1.10 percent last week.

The three-month rate was the highest since those bills averaged 1.25 percent on Oct. 20, 2008. The six-month rate was the highest since those bills averaged 1.40 percent on Oct. 27, 2008.

The discount rates reflect that the bills sell for less than face value. For a $10,000 bill, the three-month price was $9,974.47, while a six-month bill sold for $9,943.38. That would equal an annualized rate of 1.027 percent for the three-month bills and 1.142 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 1.21 percent on Friday, up from 1.19 percent at the start of last week on June 12.