The Treasury sold $6.4 billion in new three-month bills at an average discount rate of 5.74%, down from 5.85% last week. Another $6.4 billion was sold in new six-month bills at an average discount rate of 6.11%, down from 6.19% last week. The rates on three-month bills were the lowest since Dec. 28, when they sold for 5.73%. The six-month rate was the lowest since Oct. 26, when it averaged 5.98%. The new discount rates understate the actual return to investors--5.92% for three-month bills, with a $10,000 bill selling for $9,854.90 and 6.41% for six-month bills selling for $9,691.10. The discount rate reflects the price discount received when government securities are purchased at less than face value.