Interest Rates Rise in Treasury Auction

The Treasury Department auctioned $19 billion in three-month bills at a discount rate of 4.510%, up from 4.5% last week. About $21 billion in six-month bills was auctioned at a discount rate of 4.645%, up from 4.6%.

The new discount rates understate the actual return to investors -- 4.625% for three-month bills, with a $10,000 bill selling for $9,886.00, and 4.823% for a six-month bill selling for $9,765.17.

Separately, the Federal Reserve said the average yield for one-year Treasury bills, a popular index for making changes in adjustable-rate mortgages, rose to 4.77% last week from 4.74% the previous week.