Year	Percent
1991	48.544
1992	50.756
1993	52.077
1994	51.996
1995	53.401
1996	54.549
1997	52.976
1998	52.294
1999	52.403
2000	53.458
2001	50.885
2002	53.044
2003	53.479
2004	53.335
2005	52.395
2006	52.608
2007	51.689
2008	51.066
2009	50.776
2010	53.804
2011	54.607
2012	55.282
2013	55.128
2014	55.341
2015	57.303
2016	58.298
2017	58.739
2018	58.582
2019	58.565
2020	58.472
2021	58.458
2022	58.478