18 instances from 3 years 2018 - 1 instance Jan 3 Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2017 - 5 instances Jan 7 Feb Mar Apr May Jun 21 22 23 Jul Aug Sep Oct 4 Nov Dec 2016 - 12 instances Jan Feb Mar Apr May Jun 20 4 Jun 20, 2016 4 instances 13:16:47 19:30:04 21:40:11 22:42:26 Jul Aug Sep 19 4 Sep 19, 2016 4 instances 19:08:35 19:14:24 19:31:22 19:36:57 Oct 1 3 2 Oct 3, 2016 2 instances 18:08:07 19:03:44 Nov Dec 29