Year	Percent
1990	74.794
1991	74.582
1992	74.389
1993	74.155
1994	73.87
1995	73.348
1996	73.148
1997	72.796
1998	72.284
1999	71.734
2000	71.275
2001	70.947
2002	70.726
2003	70.368
2004	70.048
2005	69.761
2006	69.732
2007	69.701
2008	69.674
2009	69.652
2010	69.623
2011	69.631
2012	69.735
2013	69.851
2014	69.916
2015	69.876
2016	69.824
2017	69.855
2018	69.872
2019	69.873
2020	69.855
2021	69.821
2022	69.774
2023	69.714
2024	69.644
2025	69.567
2026	69.483
2027	69.396
2028	69.31
2029	69.234
2030	69.173