Europe vs USA: daily confirmed Covid cases

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image showing Europe vs USA: daily confirmed Covid cases

sakri on June 17th, 2020 at 14:47 UTC »

according to google EU population : 446M, USA : 328.2M

Brodie_C on June 17th, 2020 at 15:51 UTC »

Strong support line at 20,000

Gruwel on June 17th, 2020 at 17:17 UTC »

Does anyone know where this oscillation is coming from? Is it a physical cause? Or a measurement/statistical thing?