Year	Percent
1991	61.877
1992	61.729
1993	62.997
1994	64.131
1995	63.024
1996	67.555
1997	66.886
1998	66.156
1999	65.957
2000	65.109
2001	65.04
2002	64.776
2003	65.035
2004	65.163
2005	65.232
2006	64.831
2007	64.501
2008	64.593
2009	64.542
2010	64.494
2011	64.448
2012	64.453
2013	64.477
2014	64.46
2015	64.229
2016	63.954
2017	64.017
2018	64.231
2019	64.383
2020	64.507
2021	64.615
2022	64.712