Year	Percent
1990	94.248
1991	94.259
1992	94.268
1993	94.274
1994	94.274
1995	94.268
1996	94.259
1997	94.244
1998	94.228
1999	94.214
2000	94.204
2001	94.202
2002	94.202
2003	94.207
2004	94.212
2005	96.122
2006	97.356
2007	97.246
2008	97.122
2009	96.982
2010	96.826
2011	96.651
2012	97.359
2013	96.002
2014	95.995
2015	96.746
2016	96.403
2017	96.527
2018	96.65
2019	96.772
2020	96.895
2021	97.018
2022	97.142
2023	97.265
2024	97.387
2025	97.506
2026	97.624
2027	97.74
2028	97.855
2029	97.97
2030	98.086