Year	Percent
1990	82.387
1991	82.162
1992	81.999
1993	81.705
1994	81.301
1995	80.917
1996	80.515
1997	80.117
1998	79.551
1999	78.827
2000	80.841
2001	82.973
2002	85.053
2003	87.008
2004	88.783
2005	88.795
2006	88.889
2007	88.974
2008	89.047
2009	89.105
2010	89.15
2011	89.263
2012	89.35
2013	89.47
2014	89.564
2015	89.633
2016	89.656
2017	89.862
2018	90.052
2019	90.223
2020	90.373
2021	90.512
2022	90.637
2023	90.751
2024	90.858
2025	90.962
2026	91.069
2027	91.173
2028	91.282
2029	91.405
2030	91.548