Year	Percent
1991	38.611
1992	45.21
1993	48.649
1994	51.971
1995	29.23
1996	31.598
1997	32.895
1998	32.911
1999	33.459
2000	32.966
2001	36.801
2002	34.886
2003	41.535
2004	51.036
2005	59.593
2006	64.201
2007	65.909
2008	68.104
2009	69.623
2010	68.619
2011	78.729
2012	75.39
2013	71.786
2014	69.488
2015	66.791
2016	64.239
2017	64.082
2018	63.497
2019	63.885
2020	64.421
2021	65.621
2022	65.808