Year	Percent
1991	64.199
1992	64.529
1993	64.956
1994	65.126
1995	65.064
1996	64.878
1997	64.251
1998	64.008
1999	71.857
2000	72.417
2001	70.424
2002	70.932
2003	72.422
2004	73.294
2005	73.269
2006	73.98
2007	73.353
2008	71.539
2009	69.536
2010	68.021
2011	67.01
2012	66.41
2013	66.204
2014	65.83
2015	66.23
2016	51.559
2017	51.571
2018	51.58
2019	51.588
2020	51.595
2021	51.601
2022	51.606