Year	Percent
1991	47.557
1992	47.18
1993	47.206
1994	47.26
1995	47.055
1996	46.444
1997	51.238
1998	50.791
1999	50.848
2000	50.575
2001	50.362
2002	50.333
2003	49.822
2004	49.665
2005	49.528
2006	48.944
2007	48.37
2008	46.847
2009	46.152
2010	44.594
2011	44.393
2012	44.559
2013	44.411
2014	43.981
2015	44.09
2016	45.08
2017	45.302
2018	45.237
2019	45.172
2020	45.109
2021	45.043
2022	44.978