The USA, which was showing an increasing trend in Figs. 1 and 2 , displays a decreasing probability but at a lower rate and the increase in the previous figures may be attributed to the increase in the test number.
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The USA, which was showing an increasing trend in Figs. 1 and 2 , displays a decreasing probability but at a lower rate and the increase in the previous figures may be attributed to the increase in the test number.