Year	% of population
2005	36.2982399659209
2006	34.7153823911037
2007	33.0114832312896
2008	29.649556136561
2009	28.6736746841494
2010	26.4902070740999
2011	26.4814356064914
2012	24.6253764540837
2015	20.7664955383861
2016	18.7127215388426
2017	20.1134494942358