20 instances from 4 years 2018 - 3 instances Jan Feb Mar Apr May Jun 21 3 Jun 21, 2018 3 instances 03:29:05 03:29:40 03:30:35 Jul Aug Sep Oct Nov Dec 2017 - 4 instances Jan Feb Mar Apr May Jun 21 2 Jun 21, 2017 2 instances 20:20:44 20:23:35 Jul Aug Sep Oct 2 Nov Dec 25 2016 - 12 instances Jan Feb Mar Apr May Jun 20 4 Jun 20, 2016 4 instances 08:50:58 09:11:50 11:24:46 13:19:39 Jul Aug Sep 19 3 Sep 19, 2016 3 instances 17:14:35 17:18:14 17:20:53 Oct 1 3 3 Oct 3, 2016 3 instances 17:21:30 17:26:20 17:26:52 Nov Dec 30 2015 - 1 instance Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 18