Year	Percent
1990	86.32
1991	86.249
1992	86.555
1993	86.919
1994	86.425
1995	85.149
1996	85.398
1997	86.228
1998	86.074
1999	85.501
2000	85.059
2001	84.545
2002	84.112
2003	83.614
2004	84.13
2005	84.115
2006	84.535
2007	84.398
2008	84.005
2009	83.386
2010	83.207
2011	83.039
2012	83.393
2013	82.971
2014	82.74
2015	82.598
2016	82.538
2017	82.541
2018	82.548
2019	82.559
2020	82.571
2021	82.588
2022	82.607
2023	82.62
2024	82.615
2025	82.586
2026	82.539
2027	82.47
2028	82.384
2029	82.289
2030	82.19