Year	Percent
1991	58.27
1992	61.219
1993	55.404
1994	56.676
1995	51.557
1996	57.319
1997	53.655
1998	48.395
1999	63.117
2000	66.243
2001	60.778
2002	54.202
2003	57.844
2004	49.953
2005	50.398
2006	52.311
2007	52.131
2008	51.135
2009	51.395
2010	58.579
2011	55.753
2012	59.665
2013	57.856
2014	57.511
2015	55.73
2016	55.17
2017	55.969
2018	55.092
2019	55.702
2020	55.715
2021	56.022
2022	56.311