In the menu, select assumptions/revenues/sales models. If the top of your screen does not read “Sales Model » Customers by Marketing and Sales Effort,” press the blue “Select a New Sales Model” button at the bottom of the screen and then select “BU 3: Use Marketing and Sales to Drive New Customer Acquisition.” The seventh column of the screen contains the customer retention rate for each of the markets. Click on the values to change them. A customer retention rate of 75% means that 75% of your customers remain your customers after a year. The customer attrition rate is 100% minus customer retention rate.

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How do I change sales models?