Year	Percent
1985	0.01227
1990	0.1
1991	0.2
1992	0.2
1993	0.2
1994	0.3
1995	0.4
1996	0.4
1997	0.5
1998	0.6
1999	0.7
2000	0.7
2001	0.8
2002	0.8
2003	0.8
2004	0.8
2005	0.8
2006	0.8
2007	0.8
2008	0.8
2009	0.6
2010	0.6
2011	0.6