Chart description: The graph presents a steep decrease in flight frequency around the month of March, rapidly falling from above 0 to approximately -0.7. A steep increase can be observed starting a little before April and ascending in a non-linear manner with short plateaus and decreases until the month of October when it reaches above 0. After October the frequency decreases slightly to a little below 0 and remains fairly steady.

Chart data: Week starting on China Jan 05, 2020 0.078 Jan 12, 2020 0.088 Jan 19, 2020 0.016 Jan 26, 2020 −0.005 Feb 02, 2020 −0.227 Feb 09, 2020 −0.633 Feb 16, 2020 −0.708 Feb 23, 2020 −0.623 Mar 01, 2020 −0.416 Mar 08, 2020 −0.429 Mar 15, 2020 −0.387 Mar 22, 2020 −0.375 Mar 29, 2020 −0.439 Apr 05, 2020 −0.462 Apr 12, 2020 −0.426 Apr 19, 2020 −0.424 Apr 26, 2020 −0.392 May 03, 2020 −0.32 May 10, 2020 −0.274 May 17, 2020 −0.288 May 24, 2020 −0.27 May 31, 2020 −0.198 Jun 07, 2020 −0.212 Jun 14, 2020 −0.179 Jun 21, 2020 −0.239 Jun 28, 2020 −0.212 Jul 05, 2020 −0.225 Jul 12, 2020 −0.146 Jul 19, 2020 −0.107 Jul 26, 2020 −0.109 Aug 02, 2020 −0.108 Aug 09, 2020 −0.105 Aug 16, 2020 −0.08 Aug 23, 2020 −0.066 Aug 29, 2020 −0.062 Sep 06, 2020 −0.033 Sep 13, 2020 −0.042 Sep 20, 2020 −0.023 Sep 27, 2020 0.011 Oct 04, 2020 0.021 Oct 11, 2020 −0.002 Oct 18, 2020 −0.015 Oct 25, 2020 −0.035 Nov 01, 2020 −0.03 Nov 08, 2020 −0.032 Nov 15, 2020 −0.019 Nov 22, 2020 −0.021 Nov 29, 2020 −0.022 Dec 06, 2020 −0.022 Dec 13, 2020 −0.03 Dec 21, 2020 −0.038

Vega-Lite specification:
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