Year	Percent
1990	73.193
1991	73.447
1992	74.361
1993	75.009
1994	75.286
1995	75.338
1996	75.419
1997	75.45
1998	75.43
1999	75.361
2000	74.492
2001	73.653
2002	72.856
2003	72.096
2004	71.36
2005	70.646
2006	69.955
2007	69.294
2008	69.797
2009	70.312
2010	70.84
2011	71.331
2012	71.58
2013	72.017
2014	72.502
2015	72.781
2016	73.993
2017	73.909
2018	73.808
2019	73.697
2020	73.575
2021	73.445
2022	73.303
2023	73.142
2024	72.948
2025	72.717
2026	72.448
2027	72.127
2028	71.789
2029	71.492
2030	71.273