Year	Percent
1980	0.018
1981	0.017
1982	0.017
1983	0.018
1984	0.018
1985	0.018
1986	0.017
1987	0.017
1988	0.017
1989	0.016
1990	0.017
1991	0.018
1992	0.015
1993	0.016
1994	0.014
1995	0.015
1996	0.016
1997	0.016
1998	0.016
1999	0.016
2000	0.015
2001	0.015
2002	0.014
2003	0.015
2004	0.015
2005	0.014
2006	0.014
2007	0.015
2008	0.016
2009	0.017
2010	0.017
2011	0.017
2012	0.017
2013	0.017
2014	0.018
2015	0.018
2016	0.018
2017	0.018
2018	0.017
2019	0.018
2020	0.018
2021	0.018
2022	0.019
2023	0.019
2024	0.02