Aggregate Units of Production Defining an aggregate unit of production at higher level of the firm is more difficult: When the firm produces a large of products,a natural aggregate unit is sales dollars; Aggregate planning is closely related to hierarchical production planning (HPP).HPP considers workforce sizes and production rates at different levels of the firm.The recommended hierarchy is as follows: vItems-correspond to individual models of washing machines; Families-a group of items,e.g.all washing machines; Types-groups of families,e.g.large house appliances;Aggregate Units of Production • Defining an aggregate unit of production at higher level of the firm is more difficult; • When the firm produces a large of products, a natural aggregate unit is sales dollars; • Aggregate planning is closely related to hierarchical production planning (HPP). HPP considers workforce sizes and production rates at different levels of the firm. The recommended hierarchy is as follows:  Items-correspond to individual models of washing machines;  Families-a group of items, e.g. all washing machines;  Types-groups of families, e.g. large house appliances;