The METRIC.lng Model Multi-echelon Inventory View the model Download the model This model estimates the average number of backorders in a two level inventory system composed of a single depot or distribution center and any number of outlets served by the depot. Inventory policy at each location is described by a single number S. Whenever the sum of the amount on hand and on order drops below S, an order is placed to bring inventory back up to S. This is an evaluation model, rather than an optimization model. The user is prompted for the S values (SDEPOT and SOUTLET). Keywords: Demand Backlog | Distribution | Forecasting | Inventory | Product Management | Production | Reorder Point | Shipping