Year	Percent (Units)
1992	0.039
1993	0.038
1994	0.025
1995	0.024
1996	0.022
1997	0.021
1998	0.019
1999	0.018
2000	0.018
2001	0.018
2002	0.019
2003	0.020
2004	0.020
2005	0.021
2006	0.021
2007	0.020
2008	0.021
2009	0.020
2010	0.020
2011	0.021
2012	0.021
2013	0.023
2014	0.023
2015	0.023
2016	0.026
2017	0.026
2018	0.026
2019	0.026
2020	0.025
2021	0.026
2022	0.024
2023	0.024
2024	0.024
2025	0.024
2026	0.024
2027	0.025
2028	0.025
2029	0.026