Year	Percent
1991	37.922
1992	37.74
1993	37.719
1994	36.159
1995	35.94
1996	35.874
1997	35.848
1998	35.403
1999	37.293
2000	39.355
2001	39.174
2002	36.008
2003	38.937
2004	46.734
2005	47.634
2006	49.407
2007	50.606
2008	55.31
2009	58.484
2010	65.643
2011	63.952
2012	61.657
2013	59.443
2014	60.783
2015	61.465
2016	61.635
2017	61.651
2018	61.839
2019	62.076
2020	62.669
2021	63.298
2022	63.875