Year	Percent
1990	88.05
1991	88.018
1992	88.145
1993	88.307
1994	88.463
1995	88.57
1996	88.607
1997	88.567
1998	88.47
1999	88.382
2000	88.356
2001	88.398
2002	88.446
2003	88.275
2004	87.959
2005	88.701
2006	89.404
2007	90.069
2008	90.699
2009	90.523
2010	90.922
2011	91.12
2012	91.303
2013	91.475
2014	90.715
2015	89.881
2016	89.874
2017	90.132
2018	90.397
2019	90.67
2020	90.949
2021	91.236
2022	91.532
2023	91.833
2024	92.134
2025	92.43
2026	92.721
2027	93.01
2028	93.291
2029	93.561
2030	93.819