Year	Percent
1980	0.011
1981	0.012
1982	0.011
1983	0.012
1984	0.011
1985	0.012
1986	0.012
1987	0.012
1988	0.012
1989	0.012
1990	0.012
1991	0.012
1992	0.011
1993	0.01
1994	0.01
1995	0.008
1996	0.008
1997	0.007
1998	0.007
1999	0.007
2000	0.007
2001	0.007
2002	0.007
2003	0.007
2004	0.007
2005	0.007
2006	0.007
2007	0.007
2008	0.007
2009	0.007
2010	0.007
2011	0.007
2012	0.007
2013	0.007
2014	0.007
2015	0.007
2016	0.007
2017	0.006
2018	0.006
2019	0.006
2020	0.006
2021	0.006
2022	0.005
2023	0.005
2024	0.005