Year	Percent
1990	57.822
1991	58.172
1992	58.806
1993	59.461
1994	59.858
1995	60.479
1996	61.183
1997	60.901
1998	61.469
1999	62.142
2000	62.361
2001	62.088
2002	62.428
2003	64.118
2004	63.97
2005	64.497
2006	64.571
2007	64.934
2008	65.127
2009	65.572
2010	65.676
2011	65.631
2012	66.12
2013	66.772
2014	66.977
2015	67.178
2016	67.43
2017	67.612
2018	67.789
2019	67.968
2020	68.154
2021	68.33
2022	68.507
2023	68.695
2024	68.902
2025	69.135
2026	69.379
2027	69.65
2028	69.942
2029	70.244
2030	70.547