Use this session to ratio history
		  data.
      Field Information
   
   
   
      
         - 
            Remove History to year
         
 
         - 
            
Enter the year up to which history must be deleted.
          
      
      
         - 
            Ratio
         
 
         - 
            
The first ratio in the range.
          
      
      
         - 
            Ratio
         
 
         - 
            
The last ratio in the range.
          
      
      
         - 
            Backup File
         
 
         - 
            
Enter a location for a backup file.