Year	Percent
1990	91.217
1991	91.556
1992	91.936
1993	92.371
1994	92.543
1995	92.583
1996	92.695
1997	92.88
1998	92.959
1999	93.087
2000	93.274
2001	93.391
2002	93.406
2003	93.372
2004	93.314
2005	93.263
2006	93.255
2007	93.218
2008	93.174
2009	93.192
2010	93.126
2011	93.085
2012	93.029
2013	92.938
2014	92.825
2015	92.74
2016	92.759
2017	92.727
2018	92.696
2019	92.667
2020	92.639
2021	92.61
2022	92.583
2023	92.556
2024	92.527
2025	92.495
2026	92.458
2027	92.419
2028	92.379
2029	92.338
2030	92.297