Year	Percent
1990	96.696
1991	95.793
1992	94.445
1993	95.289
1994	94.676
1995	94.196
1996	94.715
1997	94.86
1998	95.541
1999	94.334
2000	94.512
2001	94.482
2002	94.456
2003	94.429
2004	94.398
2005	94.361
2006	94.319
2007	94.279
2008	94.243
2009	94.214
2010	94.665
2011	94.244
2012	94.676
2013	94.911
2014	94.827
2015	94.694
2016	94.547
2017	94.554
2018	94.557
2019	94.559
2020	94.561
2021	94.561
2022	94.562
2023	94.56
2024	94.557
2025	94.552
2026	94.546
2027	94.542
2028	94.54
2029	94.543
2030	94.548
