Year	Percent
1991	46.9
1992	47.594
1993	48.627
1994	48.709
1995	50.627
1996	50.233
1997	49.883
1998	50.999
1999	51.793
2000	52.043
2001	52.039
2002	51.291
2003	50.574
2004	51.94
2005	52.031
2006	52.055
2007	50.07
2008	51.028
2009	50.349
2010	49.987
2011	51.494
2012	51.89
2013	51.298
2014	51.541
2015	51.411
2016	49.5
2017	49.638
2018	49.718
2019	49.757
2020	49.732
2021	49.532
2022	49.305