Use this tab to define income types for the delivery address of the customer. 
A customer income type identifies the category of income each invoice line from 
the customer represents, e.g., miscellaneous income, rents, or royalties. This 
information is used to withhold taxes. 
Income types and descriptions are defined per country in the Enterprise/Tax/Income 
Types window. You can select income types connected to country and the 
accounting currency of the company.