Year	Percent
1990	75.241
1991	75.26
1992	75.222
1993	75.036
1994	75.051
1995	74.716
1996	74.42
1997	74.368
1998	74.126
1999	73.746
2000	73.562
2001	73.161
2002	72.747
2003	72.303
2004	71.856
2005	71.397
2006	70.936
2007	70.517
2008	70.098
2009	69.683
2010	69.248
2011	68.808
2012	68.365
2013	68.133
2014	67.941
2015	67.842
2016	67.797
2017	67.737
2018	67.676
2019	67.613
2020	67.547
2021	67.457
2022	67.365
2023	67.27
2024	67.171
2025	67.068
2026	66.944
2027	66.817
2028	66.691
2029	66.571
2030	66.46