Rates mixed at weekly US Treasury bill auction; 3-month bills stay at lowest level since 2011

Interest rates on short-term Treasury bills were mixed in Monday's auction, with rates on three-month bills holding at their lowest level since late 2011 while rates on six-month bills declined.

The Treasury Department auctioned $24 billion in three-month bills at a discount rate of 0.010 percent, unchanged from last week. Another $24 billion in six-month bills was auctioned at a discount rate of 0.080 percent, down from 0.100 percent last week.

The three-month rate was the lowest since three-month bills averaged 0.005 percent on Dec. 19, 2011. The six-month rate was the lowest since these bills averaged 0.070 percent on June 1.

The discount rates reflect that the bills sell for less than face value. For a $10,000 bill, the three-month price was $9,999.74, while a six-month bill sold for $9,995.95. That would equal an annualized rate of 0.010 percent for the three-month bills and 0.081 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, slipped to 0.27 percent from 0.28 percent the previous week.