Year	Percent
1990	92.324
1991	92.433
1992	92.51
1993	92.533
1994	92.488
1995	92.431
1996	92.337
1997	92.257
1998	92.348
1999	92.322
2000	92.251
2001	92.219
2002	92.16
2003	92.056
2004	91.895
2005	91.543
2006	91.204
2007	91.01
2008	91.672
2009	91.564
2010	91.326
2011	91.508
2012	91.187
2013	90.855
2014	91.462
2015	90.879
2016	90.632
2017	90.581
2018	90.531
2019	90.484
2020	90.442
2021	90.403
2022	90.37
2023	90.34
2024	90.313
2025	90.289
2026	90.265
2027	90.243
2028	90.223
2029	90.204
2030	90.185