Year	Percent
1990	89.228
1991	89.196
1992	89.207
1993	89.172
1994	89.399
1995	89.577
1996	89.876
1997	90.202
1998	90.403
1999	90.637
2000	90.847
2001	90.906
2002	90.974
2003	91.082
2004	91.166
2005	91.232
2006	91.239
2007	90.329
2008	89.328
2009	88.227
2010	87.018
2011	85.694
2012	85.754
2013	85.828
2014	85.939
2015	86.074
2016	86.217
2017	85.954
2018	85.691
2019	85.425
2020	85.154
2021	84.88
2022	84.601
2023	84.318
2024	84.029
2025	83.736
2026	83.439
2027	83.138
2028	82.835
2029	82.529
2030	82.222