Year	Percent
1990	94.469
1991	94.509
1992	94.551
1993	94.596
1994	94.617
1995	94.633
1996	94.614
1997	94.593
1998	94.565
1999	94.553
2000	94.531
2001	94.482
2002	94.424
2003	94.378
2004	94.334
2005	94.299
2006	94.262
2007	94.221
2008	94.198
2009	94.203
2010	94.191
2011	94.175
2012	94.164
2013	94.159
2014	94.154
2015	94.149
2016	94.156
2017	94.156
2018	94.154
2019	94.151
2020	94.146
2021	94.136
2022	94.124
2023	94.109
2024	94.091
2025	94.069
2026	94.041
2027	94.009
2028	93.975
2029	93.942
2030	93.911
