Year	% of total
1990	99.1295375523623
1995	99.1928768443092
2000	97.8822939845548
2005	99.5309842288025
2010	99.1553802400232
2011	99.1884381132616
2012	98.9887615131308
2013	98.622271319786
2014	96.167389318452
2015	96.1587852969623
2016	92.7859400539091
2017	93.3489958907002