Year	Percent
1990	94.938
1991	94.899
1992	94.874
1993	94.801
1994	94.671
1995	94.499
1996	94.358
1997	94.312
1998	94.213
1999	94.122
2000	93.488
2001	92.781
2002	91.994
2003	91.119
2004	90.147
2005	89.069
2006	88.943
2007	88.837
2008	88.894
2009	88.867
2010	88.701
2011	88.573
2012	88.445
2013	88.266
2014	88.091
2015	87.912
2016	87.709
2017	87.684
2018	87.657
2019	87.618
2020	87.562
2021	87.491
2022	87.406
2023	87.313
2024	87.218
2025	87.127
2026	87.04
2027	86.955
2028	86.872
2029	86.79
2030	86.708