Rates on 3-, 6-Month T-Bills Mixed in Auction

The Treasury Department auctioned $17 billion in three-month bills at a discount rate of 4.975%, the same as last week. An additional $15 billion in six-month bills was auctioned at a discount rate of 4.975%, down from 5.060% last week.

The discount rates understate the true annualized yields on the bills -- 5.11% for the three-month bills and 5.17% for the six-month bills.

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 5.17% last week from 5.22% the previous week.