Method of determining inventory levels

A computer-readable medium executing a method of determining desired stock levels is provided. Demand histories, including peak demands, for each of a plurality of items are determined. The items are ranked, based on unit price, to produce a ranked list, which is divided into price percentiles. Multipliers are assigned to each of the items, based on the respective price percentiles, and stock levels are determined for each of the items by multiplying the peak demand of each item and the respective assigned multiplier. Order quantities are assigned to each of the items based on price percentiles. A service level metric and a resource metric are determined based on the stock levels and the respective order quantities, and the service level metric and resource metric are compared with a desired service level range and a desired resource metric range to determine whether the determined stock levels are the desired stock levels.