Year	Percent
1979	0.04212
1990	0.9
1991	1.2
1992	1.6
1993	2
1994	2.6
1995	3.1
1996	3.7
1997	4.2
1998	4.6
1999	4.9
2000	5.2
2001	5.3
2002	5.4
2003	5.4
2004	5.4
2005	5.4
2006	5.4
2007	5.3
2008	5.3
2009	5.2
2010	5.1
2011	5