Grade Rate - Create New or Use Existing

Summary

When creating new grades, is it best practice to use the existing Grade Rate or create a new one?

Content

Hello All:

When creating new grades, is it best practice to use the existing Grade Rate or create a new one?

Scenario: A new grade structure is being created. New grades, new mid, min and max values for each.  The old grades currently use a Grade Rate that is a rate type of 'Salary', frequency is 'Annually' and currency is 'USD'. The new grades will use the exact same details.  Do we need to create a new Grade Rate or can we just inactivate the current grades attached to the current grade rate and add the new grades to it? What is best practice?