20 instances from 4 years 2020 - 1 instance Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov 13 Dec 2018 - 3 instances Jan 6 Feb Mar Apr May Jun 22 27 Jul Aug Sep Oct Nov Dec 2017 - 4 instances Jan 8 Feb Mar Apr May Jun 23 Jul Aug Sep Oct 5 Nov Dec 25 2016 - 12 instances Jan Feb Mar Apr May Jun 21 22 Jul Aug Sep 20 4 Sep 20, 2016 4 instances 16:01:20 16:50:26 21:32:16 21:49:47 Oct 1 2 Oct 1, 2016 2 instances 22:42:34 23:55:19 4 3 Oct 4, 2016 3 instances 17:21:49 17:49:26 20:27:47 Nov Dec 30