Chart description: April was the worst month for the frequency of flights.

Chart data: Week starting on South Korea Jan 05, 2020 0.018 Jan 12, 2020 0.021 Jan 19, 2020 0.034 Jan 26, 2020 0.014 Feb 02, 2020 −0.034 Feb 09, 2020 −0.093 Feb 16, 2020 −0.157 Feb 23, 2020 −0.179 Mar 01, 2020 −0.341 Mar 08, 2020 −0.521 Mar 15, 2020 −0.561 Mar 22, 2020 −0.557 Mar 29, 2020 −0.566 Apr 05, 2020 −0.593 Apr 12, 2020 −0.605 Apr 19, 2020 −0.588 Apr 26, 2020 −0.485 May 03, 2020 −0.495 May 10, 2020 −0.507 May 17, 2020 −0.491 May 24, 2020 −0.487 May 31, 2020 −0.461 Jun 07, 2020 −0.508 Jun 14, 2020 −0.505 Jun 21, 2020 −0.505 Jun 28, 2020 −0.495 Jul 05, 2020 −0.499 Jul 12, 2020 −0.487 Jul 19, 2020 −0.467 Jul 26, 2020 −0.423 Aug 02, 2020 −0.415 Aug 09, 2020 −0.411 Aug 16, 2020 −0.402 Aug 23, 2020 −0.402 Aug 29, 2020 −0.438 Sep 06, 2020 −0.52 Sep 13, 2020 −0.487 Sep 20, 2020 −0.464 Sep 27, 2020 −0.36 Oct 04, 2020 −0.409 Oct 11, 2020 −0.421 Oct 18, 2020 −0.402 Oct 25, 2020 −0.394 Nov 01, 2020 −0.387 Nov 08, 2020 −0.453 Nov 15, 2020 −0.409 Nov 22, 2020 −0.402 Nov 29, 2020 −0.439 Dec 06, 2020 −0.483 Dec 13, 2020 −0.503 Dec 21, 2020 −0.484

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