SQL Server - Do automatically created column statistics get dropped automatically after time? The retired SQL Server 2000 documentation https://www.microsoft.com/en-us/download/details.aspx?id=51958 states:  


  "The statistics generated for a column can be deleted if you no longer
  want to retain and maintain them. Statistics created on columns by SQL
  Server (when the AUTO_CREATE_STATISTICS database option is set to ON)
  are aged and dropped automatically."


Obviously this is old documentation related to SQL Server 2000, but I can't find anything official that is more current and says otherwise or that the behaviour is different now.  Can anyone answer definitively?  Thanks..
SQL Server, under no version or circumstance, will automatically remove statistics objects, unless the underlying object (table/view/index) is removed.

Use DROP STATISTICS ... T-SQL or use the SSMS GUI to drop unnecessary statistics, but only do that if you are certain they are not needed.