Year	Percent
1980	0.016
1981	0.015
1982	0.015
1983	0.014
1984	0.014
1985	0.014
1986	0.014
1987	0.013
1988	0.014
1989	0.014
1990	0.014
1991	0.014
1992	0.012
1993	0.01
1994	0.011
1995	0.012
1996	0.011
1997	0.011
1998	0.011
1999	0.011
2000	0.01
2001	0.01
2002	0.01
2003	0.01
2004	0.01
2005	0.009
2006	0.009
2007	0.008
2008	0.008
2009	0.009
2010	0.009
2011	0.009
2012	0.009
2013	0.009
2014	0.01
2015	0.01
2016	0.01
2017	0.01
2018	0.01
2019	0.011
2020	0.011
2021	0.011
2022	0.011
2023	0.011
2024	0.011