However there is clearly some variation with the extreme swings being approximately ± 25 per cent of average sales. But the orders placed on the suppliers are much amplified. Now the extreme swings are roughly ± 50 per cent of average sales. In other words, based on deviations about the average, the bullwhip evident in this simple scenario is already 2:1 across just one business interface. However the realities for the transportation process are much more extreme. For example, if the supplier delivers exactly what is ordered by the retailer, his lorry requirements will vary not by 2:1, but by 3:1, that is the capacity needed could drop as low as that provided by (say) two lorries/day but can rise as high as six lorries/day. In contrast, if the supplier was required to replenish sales as they actually occur, four lorries would be adequate for most deliveries, a conclusion readily exploited in industrial practice via vendor management inventory (VMI) systems (Disney et al, 2003).