Year	Percent
1990	92.029
1991	92.047
1992	92.068
1993	92.082
1994	92.103
1995	92.119
1996	92.135
1997	92.161
1998	92.183
1999	91.095
2000	90.44
2001	90.352
2002	90.597
2003	92.052
2004	90.744
2005	89.927
2006	88.398
2007	87.642
2008	87.245
2009	87.985
2010	88.941
2011	90.635
2012	90.519
2013	90.668
2014	90.834
2015	90.37
2016	90.215
2017	90.207
2018	90.199
2019	90.186
2020	90.165
2021	90.137
2022	90.099
2023	90.051
2024	89.995
2025	89.933
2026	89.865
2027	89.791
2028	89.712
2029	89.635
2030	89.562