20 instances from 4 years 2018 - 3 instances Jan Feb Mar Apr May Jun 21 3 Jun 21, 2018 3 instances 03:36:23 03:37:07 03:38:03 Jul Aug Sep Oct Nov Dec 2017 - 4 instances Jan Feb Mar Apr May Jun 21 2 Jun 21, 2017 2 instances 20:24:03 20:26:51 Jul Aug Sep Oct 2 Nov Dec 25 2016 - 12 instances Jan Feb Mar Apr May Jun 20 4 Jun 20, 2016 4 instances 08:56:36 09:17:07 11:23:44 13:25:25 Jul Aug Sep 19 3 Sep 19, 2016 3 instances 17:17:52 17:21:30 17:24:17 Oct 1 3 3 Oct 3, 2016 3 instances 17:24:46 17:29:36 17:30:09 Nov Dec 30 2015 - 1 instance Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 18