Year	Percent
1990	93.907
1991	93.654
1992	92.084
1993	91.854
1994	91.113
1995	90.331
1996	90.298
1997	90.335
1998	90.422
1999	90.497
2000	90.369
2001	90.614
2002	90.926
2003	91.557
2004	91.756
2005	91.307
2006	91.371
2007	91.033
2008	91.02
2009	90.007
2010	89.424
2011	89.273
2012	89.409
2013	88.371
2014	87.747
2015	87.794
2016	88.281
2017	88.207
2018	88.129
2019	88.05
2020	87.971
2021	87.892
2022	87.815
2023	87.739
2024	87.66
2025	87.576
2026	87.485
2027	87.387
2028	87.284
2029	87.177
2030	87.071