Year	% of population
2000	2.5
2001	2.5
2002	2.5
2003	2.9
2004	3.3
2005	3.4
2006	3.4
2007	3.4
2008	3.5
2009	3.8
2010	4.5
2011	5.9
2012	7.6
2013	9.4
2014	10.5
2015	11.1
2016	11.2
2017	11