The Treasury Department sold $6.8 billion in new three-month bills at an average discount rate of 6.97%, down from 7.18% last week. Another $6.8 billion was sold in six-month bills at an average discount rate of 7.03%, down from 7.23% last week. The rates were the lowest since three-month bills sold for 6.92% on Jan. 27 and six-month bills averaged 7.01% on Dec. 16. The new discount rates understate the actual return to investors--7.19% for three-month bills with a $10,000 bill selling for $9,823.80 and 7.39% for six-month bills selling for $9,644.60. The discount rate reflects the price discount received when government securities are purchased at less than face value.