Year	Percent
1991	56.149
1992	55.281
1993	54.047
1994	59.3
1995	59.903
1996	59.755
1997	58.465
1998	58.06
1999	58.43
2000	59.89
2001	59.868
2002	58.944
2003	57.721
2004	57.419
2005	57.153
2006	56.685
2007	57.3
2008	56.201
2009	56.299
2010	56.532
2011	57.558
2012	56.534
2013	57.125
2014	57.488
2015	57.333
2016	57.496
2017	58.86
2018	59.076
2019	59.243
2020	59.396
2021	59.518
2022	59.677