Year	Percent
1991	54.392
1992	54.72
1993	56.76
1994	56.771
1995	55.897
1996	55.412
1997	55.34
1998	54.882
1999	54.97
2000	55.016
2001	54.926
2002	54.957
2003	54.781
2004	55.262
2005	54.742
2006	52.693
2007	51.556
2008	51.382
2009	50.758
2010	51.267
2011	51.929
2012	50.394
2013	49
2014	49.702
2015	49.064
2016	49.854
2017	49.563
2018	49.463
2019	49.256
2020	49.016
2021	48.785
2022	48.564