Year	Percent
1991	47.644
1992	49.177
1993	49.079
1994	46.235
1995	71.337
1996	69.141
1997	70.717
1998	68.92
1999	71.096
2000	67.363
2001	65.903
2002	66.123
2003	65.938
2004	68.37
2005	68.078
2006	66.325
2007	65.603
2008	65.815
2009	65.849
2010	64.831
2011	66.157
2012	65.56
2013	65.267
2014	65.287
2015	64.866
2016	65.067
2017	64.966
2018	64.864
2019	64.759
2020	64.654
2021	64.547
2022	64.44