The 1.1% decline was the biggest drop in eight months, the Commerce Department said. The department said American business sales totaled $427.2 billion in February, down $4.77 billion from January. It was the biggest fall in sales since a 1.7% plunge last June. While sales were falling, inventories held on shelves and back lots edged up $163 million to $585.1 billion, a barely perceptible increase of less than 0.1%. The gain in inventories was attributed mainly to an increase in the backlog of unsold new cars.