Year	Percent
1991	48.144
1992	48.96
1993	48.906
1994	48.85
1995	48.62
1996	47.652
1997	46.045
1998	44.145
1999	44.619
2000	44.451
2001	44.739
2002	45.05
2003	46.057
2004	46.916
2005	47.708
2006	48.933
2007	49.307
2008	48.509
2009	47.737
2010	47.057
2011	46.961
2012	47.212
2013	45.616
2014	46.281
2015	46.521
2016	47.313
2017	48.075
2018	48.376
2019	48.771
2020	49.1
2021	49.422
2022	49.681