Year	Percent
1991	70.446
1992	69.334
1993	68.608
1994	67.831
1995	67.092
1996	65.471
1997	63.043
1998	59.244
1999	58.393
2000	57.546
2001	57.267
2002	57.692
2003	58.18
2004	64.468
2005	64.12
2006	63.727
2007	64.445
2008	64.894
2009	64.59
2010	64.157
2011	64.731
2012	72.065
2013	76.296
2014	71.59
2015	72.497
2016	72.213
2017	72.134
2018	72.471
2019	72.795
2020	73.148
2021	73.428
2022	73.755