Year	Percent (Units)
1980	0.002
1981	0.002
1982	0.002
1983	0.002
1984	0.003
1985	0.003
1986	0.003
1987	0.003
1988	0.003
1989	0.003
1990	0.003
1991	0.003
1992	0.003
1993	0.003
1994	0.003
1995	0.004
1996	0.004
1997	0.004
1998	0.004
1999	0.005
2000	0.005
2001	0.004
2002	0.005
2003	0.005
2004	0.005
2005	0.004
2006	0.005
2007	0.005
2008	0.005
2009	0.005
2010	0.005
2011	0.005
2012	0.005
2013	0.006
2014	0.006
2015	0.007
2016	0.007
2017	0.007
2018	0.008
2019	0.008
2020	0.006
2021	0.007
2022	0.008
2023	0.008
2024	0.008
2025	0.008
2026	0.009
2027	0.009
2028	0.009
2029	0.009