Year	Percent
1991	61.963
1992	62.398
1993	62.461
1994	62.284
1995	62.688
1996	62.743
1997	63.546
1998	63.139
1999	63.277
2000	63.755
2001	63.873
2002	63.787
2003	63.989
2004	63.839
2005	63.978
2006	64.149
2007	63.863
2008	62.961
2009	62.484
2010	62.546
2011	63.244
2012	63.794
2013	63.416
2014	63.707
2015	63.825
2016	63.851
2017	63.446
2018	63.496
2019	63.701
2020	63.841
2021	64.014
2022	64.191