Editing Reusable Rules 
Edit fixed values, translation rules, and user-defined routines.
Prerequisites
To be able to edit reusable rules, you have to create them in step Maintain Field Mapping and Conversion Rules first.
Features
You can:
Edit fixed values
Define the type of translation
Define 1:1 translation values
Define interval translation values
Activities
You can edit the corresponding rule after positioning the cursor on that rule in the change mode in step Maintain Fixed Values, Translations, and User-Defined Routines.