Interest rates on short-term Treasury bills were unchanged in Monday's auction.
The Treasury Department auctioned $30 billion in three-month bills at a discount rate of 0.065 percent. Another $31 billion in six-month bills was auctioned at a discount rate of 0.165 percent.
The three-month rate remained the highest since those bills averaged 0.075 percent on Oct. 26. The six-month rate remained the lowest since those bills averaged 0.150 percent on Oct. 13.
Both three- and six-month bills remain at historically low levels as the recession has cut demand for credit among consumers and businesses. The rates also reflect efforts by the Federal Reserve to keep a key short-term borrowing rate at a record low in an effort to help the economy recover.
Fed officials have said they plan to keep rates at exceptionally low levels for an "extended period" to provide more support for the wobbly economy. Fed Chairman Ben Bernanke reiterated that pledge on Monday in a speech in New York.
The discount rates reflect that the bills sell for less than face value. For a $10,000 bill, the three-month price was $9,998.36, while a six-month bill sold for $9,991.66. That would equal an annualized rate of 0.066 percent for the three-month bills, and 0.167 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, fell to 0.33 percent last week from 0.36 percent the previous week.