Year	Percent
1990	92.644
1991	92.376
1992	91.711
1993	90.802
1994	90.241
1995	88.957
1996	88.539
1997	88.497
1998	88.806
1999	89.095
2000	89.091
2001	88.8
2002	88.253
2003	87.67
2004	87.118
2005	86.843
2006	86.761
2007	86.953
2008	87.244
2009	87.52
2010	87.613
2011	87.636
2012	87.49
2013	87.282
2014	87.003
2015	86.717
2016	86.387
2017	86.278
2018	86.162
2019	86.036
2020	85.898
2021	85.758
2022	85.614
2023	85.469
2024	85.328
2025	85.194
2026	85.075
2027	84.966
2028	84.868
2029	84.785
2030	84.718