Future indicators for truck freight According to the Bob Costello, chief economist at the American Trucking Associations, total business inventories, relative to sales, remained very lean in June as the important inventory-to-sales (I/S) ratio fell to an all-time low. A low I/S ratio indicates that businesses are effectively managing inventories. It also suggest that once economic activity picks up, truck freight is likely to grow faster than if inventories were bloated (relative to sales), and they had to work off those supplies.               return