Year	Percent
1990	75.717
1991	75.739
1992	75.7
1993	75.519
1994	75.517
1995	75.193
1996	74.897
1997	74.823
1998	74.573
1999	74.196
2000	73.996
2001	73.575
2002	73.136
2003	72.685
2004	72.229
2005	71.773
2006	71.344
2007	70.908
2008	70.468
2009	70.026
2010	69.581
2011	69.132
2012	68.684
2013	68.458
2014	68.27
2015	68.168
2016	68.125
2017	68.076
2018	68.026
2019	67.975
2020	67.92
2021	67.844
2022	67.765
2023	67.684
2024	67.599
2025	67.509
2026	67.399
2027	67.285
2028	67.172
2029	67.066
2030	66.969