Discount chains, which posted a 5% jump, had their best performance since March 2004, when sales increased 6.3%. Target, as it has for the last three months, led the way with an 8.2% climb. Wal-Mart's discount stores followed, rising 4.8%; ShopKo fared the worst, dropping by 0.6%.

Another sector that posted a strong performance was drug stores, registering an 8.3% rise. Walgreens had the best results, soaring 11.6%, while Rite Aid only inched up 1.6%, though it bettered February's 0.6% year-on-year performance.

Wholesale clubs' 4.7% push was below their 2004 fiscal year average increase of 7.2% and February's 7.2% gain. Costco, as it has since October, led the sector, with a 7% climb. BJ's Wholesale, up 3%, and Wal-Marts Sam's Clubs, up 2.1%, followed.