# 17.2.3c Single-Level Where-Used List, Multilevel Where-Used List, and Summarized Where-Used List

### Continuation from previous subsection (17.2.3b).

Similar algorithms can also be used to create various types of where-used lists from the bill- of-material positions.

The single-level where-used list shows all the products that are integrated directly into a component.

Figure 17.2.3.6 shows the five single-level where-used lists implicitly defined by the example in Figure 1.2.2.2.[note 1705]

Fig. 17.2.3.6       Single-level where-used list.

Figure 17.2.3.6 contains exactly the same number of connections as Figure 17.2.3.3, that is, six. Although these are the same connections, here they are taken from the component view in Figure 17.2.3.2. In this case, the quantity per is the quantity of components integrated directly into the product. The single-level where-used list is useful because it provides a picture of a certain component.

The multilevel where-used list or indented where-used list shows, in structured form, how a component is used across all the levels, right down to the end products.

Figure 17.2.3.7 shows the multilevel where-used list for the component with item ID 387462 from the example in Figure 1.2.2.2.

Fig. 17.2.3.7       Indented where-used list (multilevel where-used list).

Here, the quantity per is the cumulative quantity of this component that is integrated into the product at this point. An indented where-used list is useful for assessing the possible consequences of a substitution, that is, the replacement of an unavailable primary product or component by a non-primary item.

The summarized where-used list is a condensed multilevel where-used list in which each product occurs only once, together with the cumulative quantity of that component incorporated into the product.

Figure 17.2.3.8 shows the summarized where-used list for the component with item ID 387462 from the example in Figure 1.2.2.2.

Fig. 17.2.3.8       Summarized where-used list (condensed multilevel where-used list).

In this case, the quantity per is the total quantity of components that are integrated into the product. A summarized where-used list is needed to draw up a procurement plan, for examp­le, or to estimate which end products will be affected by replacing an item at a lower level.