Year	Percent
1990	63.024
1991	63.989
1992	65.001
1993	65.608
1994	65.878
1995	65.872
1996	66.03
1997	66.081
1998	66.153
1999	66.213
2000	66.353
2001	66.257
2002	66.012
2003	65.638
2004	65.123
2005	64.933
2006	64.702
2007	64.458
2008	64.368
2009	64.738
2010	65.069
2011	66.385
2012	65.207
2013	66.201
2014	66.793
2015	67.186
2016	66.165
2017	66.22
2018	66.186
2019	66.035
2020	65.753
2021	65.321
2022	64.778
2023	64.139
2024	63.423
2025	62.655
2026	61.817
2027	60.941
2028	60.088
2029	59.338
2030	58.738