Year	Percent
1991	64.085
1992	63.899
1993	64.434
1994	63.308
1995	63.525
1996	63.332
1997	63.291
1998	65.041
1999	65.072
2000	63.885
2001	64.801
2002	66.415
2003	65.928
2004	66.363
2005	65.724
2006	64.853
2007	64.435
2008	64.048
2009	63.529
2010	63.188
2011	63.607
2012	63.943
2013	64.078
2014	64.279
2015	64.819
2016	64.191
2017	66.57
2018	66.298
2019	66.027
2020	65.726
2021	65.473
2022	65.255
