Year	Percent
1979	0.02653
1990	0.5
1991	0.8
1992	1
1993	1.2
1994	1.4
1995	1.6
1996	1.7
1997	1.8
1998	1.8
1999	1.9
2000	1.9
2001	1.9
2002	1.9
2003	1.9
2004	1.9
2005	1.9
2006	1.9
2007	1.9
2008	2
2009	2.1
2010	2.1
2011	2.1