Year	Percent
1991	55.596
1992	54.681
1993	56.971
1994	58.064
1995	58.065
1996	58.21
1997	58.33
1998	58.792
1999	59.034
2000	58.855
2001	59.295
2002	59.636
2003	60.522
2004	61.126
2005	61.581
2006	60.926
2007	61.94
2008	62.586
2009	62.658
2010	63.265
2011	63.827
2012	64.226
2013	64.583
2014	65.763
2015	66.002
2016	65.829
2017	65.756
2018	65.925
2019	66.065
2020	66.21
2021	66.331
2022	66.427