Rates on US Treasury bills rise at weekly auction

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

The Treasury Department auctioned $51 billion in three-month bills at a discount rate of 1.670 percent, up from 1.660 percent last week. Another $45 billion in six-month bills was auctioned at a discount rate of 1.850 percent, up from 1.830 percent last week.

The three-month rate was the highest since these bills averaged 1.690 percent on Sept. 8, 2008. The six-month rate was the highest since these bills averaged 1.900 percent on Sept. 8, 2008.

The discount rates reflect that the bills sell for less than face value. For a $10,000 bill, the three-month price was $9,957.79 while a six-month bill sold for $9,906,47. That would equal an annualized rate of 1.700 percent for the three-month bills and 1.893 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, edged down to 2.03 percent on Friday, compared to 2.06 percent on March 5.