The BASED ON field property bases the properties of a new field
    element on one that already exists.

    You must have privilege to read a field element to be able to
    base other elements upon it.

    You can use BASED ON field properties to define several fields
    related to a base field and to each other.

    You can use the BASED ON field property to give individual names
    to field elements that share the same properties. This allows you
    to uniquely refer to these field elements in record elements.

    If you want the new field to have additional properties not found
    in the base field, you can specify the additional properties in
    the DEFINE FIELD or CHANGE FIELD command.