Year	Percent
1991	64.687
1992	65.487
1993	65.348
1994	64.84
1995	64.538
1996	62.124
1997	61.733
1998	61.974
1999	61.458
2000	61.709
2001	61.864
2002	61.389
2003	61.381
2004	61.333
2005	61.865
2006	62.252
2007	62.538
2008	63.027
2009	62.961
2010	62.995
2011	63.91
2012	64.618
2013	64.994
2014	65.331
2015	65.622
2016	65.854
2017	66.049
2018	66.221
2019	66.32
2020	66.324
2021	66.251
2022	66.104