Year	Percent
1990	92.696
1991	92.782
1992	92.847
1993	92.946
1994	92.818
1995	92.745
1996	92.736
1997	92.693
1998	92.561
1999	92.604
2000	92.52
2001	92.457
2002	92.351
2003	92.339
2004	92.269
2005	92.166
2006	92.074
2007	91.902
2008	91.844
2009	91.967
2010	91.891
2011	91.76
2012	91.653
2013	91.566
2014	91.461
2015	91.333
2016	91.273
2017	91.24
2018	91.211
2019	91.181
2020	91.149
2021	91.115
2022	91.079
2023	91.044
2024	91.015
2025	90.994
2026	90.98
2027	90.971
2028	90.965
2029	90.958
2030	90.948