Year	Percent
1990	70.294
1991	70.43
1992	70.533
1993	70.679
1994	70.612
1995	70.4
1996	70.473
1997	70.546
1998	70.619
1999	70.692
2000	70.765
2001	70.838
2002	70.911
2003	70.983
2004	71.056
2005	71.128
2006	71.2
2007	69.239
2008	67.206
2009	65.106
2010	62.946
2011	60.733
2012	58.475
2013	56.181
2014	53.86
2015	53.686
2016	53.52
2017	53.27
2018	53.02
2019	52.771
2020	52.521
2021	52.271
2022	52.021
2023	51.772
2024	51.522
2025	51.272
2026	51.022
2027	50.773
2028	50.523
2029	50.273
2030	50.023