last -x shutdown

shutdown system down  3.16.0-4-amd64   Sat Aug 27 16:31 - 16:32  (00:00)    
shutdown system down  3.16.0-4-amd64   Fri Aug 26 08:10 - 08:11  (00:00)    
shutdown system down  3.16.0-4-amd64   Thu Aug 25 11:04 - 11:05  (00:00)    
shutdown system down  3.16.0-4-amd64   Tue Aug 23 09:45 - 09:46  (00:00)    
shutdown system down  3.16.0-4-amd64   Mon Aug 22 13:39 - 13:39  (00:00)    
shutdown system down  3.16.0-4-amd64   Mon Aug 22 12:19 - 12:20  (00:00)    
shutdown system down  3.16.0-4-amd64   Mon Aug 22 12:06 - 12:07  (00:00)    
shutdown system down  3.16.0-4-amd64   Mon Aug 22 12:05 - 12:05  (00:00)    
shutdown system down  3.16.0-4-amd64   Fri Aug 19 10:58 - 10:59  (00:01)    
shutdown system down  3.16.0-4-amd64   Thu Aug 18 20:05 - 20:05  (00:00)    
shutdown system down  3.16.0-4-amd64   Mon Aug  8 12:48 - 12:50  (00:01)    
shutdown system down  3.16.0-4-amd64   Tue Aug  2 10:11 - 10:11  (00:00)    

wtmp begins Tue Aug  2 10:10:40 2016
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