The Mining Data Mart - Data Mining Techniques in CRM: Inside Customer Segmentation - page 165

Figure 4.6 Grouping CDR data with the IBM SPSS Modeler Aggregate node.
the customer level, covering all customers that ever had a relationship with the
network operator. The table's contents denote the most recent updates of the
relevant information as well as the date of each record update.
Rate Plan History
The information in the rate plan table (''C_Rate_Plans''), Table 4.18, can be used
to calculate the tenure of each customer and MSISDN, each MSISDN's current
rate plan and status (open, closed), and the time of closing in the case of closed
MSISDNs. Similarly, a list of recently churned (e.g., within the previous month)
customers and MSISDNs can be easily produced.