Year	Percent
1991	47.056
1992	47.179
1993	47.215
1994	47.148
1995	46.975
1996	47.209
1997	47.244
1998	46.603
1999	45.944
2000	45.321
2001	44.971
2002	44.588
2003	44.178
2004	43.663
2005	45.929
2006	48.124
2007	49.728
2008	53.126
2009	56.537
2010	63.146
2011	61.801
2012	61.395
2013	60.988
2014	61.607
2015	55.911
2016	55.764
2017	56.22
2018	56.666
2019	57.108
2020	57.664
2021	58.232
2022	58.8