Year	Percent
1990	88.942
1991	89.345
1992	89.807
1993	90.316
1994	90.561
1995	90.733
1996	90.849
1997	90.826
1998	90.67
1999	90.631
2000	90.539
2001	90.489
2002	90.434
2003	90.452
2004	90.429
2005	90.374
2006	90.322
2007	90.21
2008	90.177
2009	90.288
2010	90.292
2011	90.284
2012	90.322
2013	90.379
2014	90.388
2015	90.329
2016	90.273
2017	90.174
2018	90.061
2019	89.974
2020	89.932
2021	89.934
2022	89.976
2023	90.03
2024	90.059
2025	90.043
2026	89.994
2027	89.909
2028	89.803
2029	89.699
2030	89.611