Year	Percent
1990	76.312
1991	75.912
1992	75.053
1993	74
1994	73.164
1995	72.765
1996	72.599
1997	72.932
1998	73.51
1999	73.993
2000	74.199
2001	74.289
2002	74.057
2003	73.639
2004	73.433
2005	73.462
2006	73.693
2007	74.164
2008	74.654
2009	75.174
2010	75.52
2011	75.717
2012	75.888
2013	75.948
2014	75.874
2015	75.705
2016	75.465
2017	75.382
2018	75.273
2019	75.155
2020	75.056
2021	75.006
2022	74.976
2023	74.958
2024	74.939
2025	74.912
2026	74.911
2027	74.914
2028	74.914
2029	74.914
2030	74.916