Year	% of total
1990	88
1995	91.4
1996	91.4
2000	91
2004	96
2005	96
2006	96
2007	97
2008	97
2009	97
2010	97
2013	98
2015	98
2016	98
2017	99.7
2018	99.4
2019	94.8