To improve your data collection performance, it is important to know how to manage your existing ranges under Admin > Data Collectors. If you are not using a set of ranges anymore, it is important to delete the unused ranges.
Exclude or Delete
You have two options, either to Exclude or to Delete a range; deleting an unused range will remove it from the set of ranges to reference, therefore improving the performance.
Deleting a range:
Go to Admin > Data Collectors.
Locate your unused range.
Select the 'Delete' option.
Deleted a range – What about the data from that range?
When a range is deleted from the list under Admin > Data Collectors, it is only telling the servers that it is not going to bother looking for those ranges anymore. The information already collected from those ranges in the past will still be part of the data set in your account. The information is part of all the collected history.