Year	Percent
1990	60.181
1991	61.09
1992	62.895
1993	63.766
1994	64.988
1995	66.21
1996	66.485
1997	66.971
1998	67.718
1999	69.13
2000	69.647
2001	69.686
2002	70.396
2003	71.045
2004	71.504
2005	71.873
2006	72.15
2007	73.217
2008	73.613
2009	74.526
2010	74.93
2011	75.318
2012	76.899
2013	77.026
2014	78.403
2015	78.076
2016	78.556
2017	78.809
2018	79.058
2019	79.302
2020	79.54
2021	79.774
2022	80.004
2023	80.234
2024	80.465
2025	80.701
2026	80.94
2027	81.184
2028	81.432
2029	81.682
2030	81.934