Year	Percent (Units)
1992	0.017
1993	0.014
1994	0.014
1995	0.015
1996	0.015
1997	0.015
1998	0.016
1999	0.016
2000	0.016
2001	0.017
2002	0.019
2003	0.021
2004	0.022
2005	0.024
2006	0.025
2007	0.027
2008	0.029
2009	0.025
2010	0.024
2011	0.024
2012	0.027
2013	0.027
2014	0.027
2015	0.026
2016	0.027
2017	0.029
2018	0.030
2019	0.031
2020	0.030
2021	0.029
2022	0.032
2023	0.034
2024	0.035
2025	0.035
2026	0.036
2027	0.036
2028	0.037
2029	0.037