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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Cumulative incidence graphs for global data and per groups of 10 countries (adjusted for length bias) including figure (a) for the global data and figure (b) for countries with n > 3000; figure (c) for countries with 1500 < n ≤3000; figure (d) for countries with 750 < n ≤ 1500.