Year	Percent
1990	71.388
1991	71.613
1992	71.629
1993	71.504
1994	70.655
1995	72.808
1996	81.199
1997	79.911
1998	78.803
1999	77.453
2000	76.061
2001	76.043
2002	72.732
2003	71.585
2004	72.073
2005	72.492
2006	74.174
2007	75.599
2008	76.579
2009	76.196
2010	76.903
2011	76.914
2012	76.954
2013	76.437
2014	77.556
2015	77.153
2016	75.978
2017	76.046
2018	76.07
2019	76.012
2020	75.85
2021	75.536
2022	75.123
2023	74.637
2024	74.112
2025	73.571
2026	72.976
2027	72.365
2028	71.773
2029	71.239
2030	70.788