Year	% of total
1986	97
1992	98
1993	97
1998	98
1999	98.2
2000	96.6
2001	98
2002	98.5
2003	98.2
2004	98.5
2005	98.5
2006	98.6
2007	98.7
2008	99.1
2009	99.1
2010	95.3
2011	98.4
2012	98.9
2013	99
2014	99.2
2015	90
2016	98.8
2017	98.7
2018	98.5
2019	99