Year	Percent
1990	65.843
1991	66.147
1992	66.436
1993	65.42
1994	64.325
1995	63.155
1996	61.98
1997	60.735
1998	59.383
1999	57.862
2000	56.144
2001	59.663
2002	59.192
2003	57.297
2004	58.585
2005	57.451
2006	60.363
2007	62.059
2008	63.011
2009	62.335
2010	62.202
2011	61.969
2012	63.135
2013	64.49
2014	65.014
2015	65.449
2016	64.669
2017	65.09
2018	65.445
2019	65.736
2020	65.966
2021	66.137
2022	66.236
2023	66.286
2024	66.331
2025	66.399
2026	66.499
2027	66.636
2028	66.795
2029	66.945
2030	67.066