Year	Percent
1990	82.728
1991	83.048
1992	83.445
1993	83.918
1994	84.42
1995	84.91
1996	85.266
1997	85.494
1998	85.719
1999	85.969
2000	84.806
2001	83.539
2002	82.163
2003	80.672
2004	79.068
2005	77.353
2006	77.504
2007	77.597
2008	77.614
2009	77.704
2010	77.914
2011	78.157
2012	78.468
2013	78.843
2014	79.229
2015	79.614
2016	80.03
2017	79.914
2018	79.803
2019	79.681
2020	79.54
2021	79.38
2022	79.202
2023	79.012
2024	78.817
2025	78.622
2026	78.425
2027	78.228
2028	78.031
2029	77.833
2030	77.634