Year	Percent
1990	78.058
1991	77.406
1992	76.7
1993	75.93
1994	75.087
1995	74.174
1996	73.299
1997	72.364
1998	71.403
1999	70.473
2000	69.608
2001	69.589
2002	69.645
2003	69.757
2004	69.906
2005	70.078
2006	70.242
2007	70.382
2008	70.66
2009	70.827
2010	71.405
2011	71.469
2012	71.646
2013	71.753
2014	71.919
2015	72.154
2016	72.406
2017	72.634
2018	72.85
2019	73.048
2020	73.223
2021	73.405
2022	73.571
2023	73.72
2024	73.86
2025	73.995
2026	74.148
2027	74.302
2028	74.448
2029	74.583
2030	74.705