Add or Modify the Date You Acquired a Customer
        To add or modify the date you acquired a customer:
        
            - Open the customer's record. 
How?- In the Home window, click Customers & Sales on the navigation pane.
 - In the Tasks pane, right-click the Customers icon and select Modify Customer from  the menu.    
 - Select a customer from the list and click OK.
 
 
            - On the Address tab, type or select 
 a Customer Since date.
 
            - Click Save 
 and Close.