Year	% of total
1990	88.0800392009571
1995	87.0942252436107
2000	86.9600632473711
2005	82.9000362845939
2010	89.1665895224751
2011	82.7803064014342
2012	84.2059011002366
2013	86.2926668046303
2014	88.8538151258146
2015	91.6331246579714
2016	91.0932949763815
2017	91.57567005142
