Unit/symbol charts

A unit chart can be used to show individual items, often using shapes or symbols to represent each individual. These charts can elicit a powerful emotional response because the representations of the data are less abstract and more easily identified as something real. For example, here is a chart showing how many customers had late shipments for each Region:

Figure 10.8: Each image represents a real person and is less abstract than circles or squares

The view was created with the following techniques:

• The view is filtered where Late Shipping is True. Late Shipping is a calculated field that determines if it took more than 14 days to ship an order. The code is as follows:

  DATEDIFF('day', [Order Date], [Ship Date]) > 14 
  

• Region has been sorted by the distinct count of Customer ID in descending order.
• Customer ID has been placed on Detail so that there is a mark for each distinct customer.
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