Leading US retailers had another month of year-on-year comparable sales declines in July, and several said they managed to maintain or improve profit margins on leaner inventory levels and reduced price markdowns.

Retail Metrics, which tracks monthly same-store sales, said on Thursday its index for July was down 4.7 per cent against the period last year. The index excludes Wal-Mart, the largest US retailer, which no longer reports monthly sales numbers.