Year	% of population
2005	40.5280302520733
2006	39.9606754142967
2007	38.8902303370332
2008	35.2005699288126
2009	33.4420960061466
2010	31.0901258297484
2011	31.5480799189202
2012	31.0564969228976
2015	23.8296346525592
2016	23.8699053666194
2017	28.4426585541833