For high priced parts in Groups 4–7, the demand type was studied more carefully. Group 4 was created for low demand parts, which can be interpreted similarly as stable demand from inventory control point of view. However, these materials have obsolescence risk due to the high material value. Group 5 contains high priced parts that have sporadic and lumpy demand, these are the most challenging cases for inventory management to forecast as sales are sporadic but sales batches can be large. As the demand is sporadic and lumpy, the demand is most likely coming from one or only a few customers that also stock the part in their warehouse. Thus it would be good to study the customer’s purchasing policy for improvement. Group 6 is formed from high priced materials that have unstable but continuous demand