Year	Percent
1991	49.214
1992	48.974
1993	48.582
1994	48.093
1995	47.965
1996	47.921
1997	48.887
1998	49.108
1999	47.92
2000	47.625
2001	47.875
2002	48.438
2003	46.747
2004	49.43
2005	49.133
2006	49.431
2007	50.368
2008	51.045
2009	50.418
2010	49.448
2011	48.074
2012	47.416
2013	46.143
2014	46.823
2015	46.813
2016	47.601
2017	47.868
2018	47.736
2019	47.504
2020	47.194
2021	46.849
2022	46.465