Year	% of population
2001	2.5
2002	2.7
2003	2.8
2004	3
2005	3.1
2006	3.3
2007	3.5
2008	3.5
2009	4.3
2010	4.7
2011	5.2
2012	5.2
2013	5.6
2014	5.9
2015	6.1
2016	5.7
2017	5.2
2018	4.4
2019	3.8
2020	3.2
2021	2.7
