Year	Percent
1991	62.114
1992	62.438
1993	62.294
1994	62.408
1995	61.761
1996	61.543
1997	61.145
1998	57.754
1999	57.527
2000	57.42
2001	57.09
2002	56.614
2003	56.679
2004	56.174
2005	55.833
2006	55.556
2007	55.113
2008	54.846
2009	52.894
2010	53.484
2011	56.055
2012	63.084
2013	58.4
2014	59.816
2015	60.085
2016	62.035
2017	61.814
2018	62.357
2019	62.408
2020	62.181
2021	61.887
2022	62.118