Year	Percent
1991	58.145
1992	58.314
1993	58.569
1994	58.306
1995	58.31
1996	51.487
1997	54.161
1998	57.853
1999	59.702
2000	58.111
2001	48.959
2002	43.756
2003	48.56
2004	47.997
2005	51.092
2006	50.816
2007	53.154
2008	50.593
2009	50.666
2010	51.101
2011	55.005
2012	54.443
2013	54.554
2014	53.184
2015	55.33
2016	55.551
2017	55.856
2018	56.508
2019	56.987
2020	57.402
2021	57.767
2022	58.083