Year	Percent
1991	52.963
1992	52.674
1993	52.37
1994	52.069
1995	51.77
1996	51.482
1997	51.198
1998	50.903
1999	50.608
2000	50.351
2001	50.031
2002	49.787
2003	49.988
2004	50.505
2005	51.01
2006	50.447
2007	49.864
2008	49.28
2009	48.738
2010	48.819
2011	48.907
2012	49.106
2013	50.152
2014	49.79
2015	49.36
2016	48.898
2017	48.771
2018	48.647
2019	48.533
2020	48.436
2021	48.35
2022	48.277