Rates drop in Treasury auction

The Treasury Department auctioned $21 billion in three-month bills at a discount rate of 4.77%, down from 4.825% last week. An additional $18 billion in six-month bills was auctioned at 4.73%, down from 4.8% last week.

The discount rates reflect that the bills sell for less than face value. For a $10,000 bill, the three-month price was $9,879.43, and a six-month bill sold for $9,760.87.

Separately, the Federal Reserve said the average yield for one-year Treasury bills, a popular index for making changes in adjustable-rate mortgages, fell to 4.83% last week, down from 4.91% the previous week.