Year	Percent
1990	88.005
1991	88.175
1992	88.387
1993	88.62
1994	88.859
1995	89.092
1996	89.074
1997	89.066
1998	89.078
1999	89.123
2000	88.878
2001	88.63
2002	88.373
2003	88.11
2004	87.846
2005	87.585
2006	87.333
2007	87.081
2008	86.825
2009	87.135
2010	87.462
2011	87.964
2012	88.474
2013	88.957
2014	89.373
2015	89.713
2016	90.096
2017	90.086
2018	90.078
2019	90.069
2020	90.061
2021	90.052
2022	90.044
2023	90.037
2024	90.033
2025	90.033
2026	90.035
2027	90.04
2028	90.049
2029	90.061
2030	90.076