Year	Years
1970	0.2
1971	0.3
1972	0.3
1973	0.3
1974	0.3
1975	0.3
1976	0.3
1977	0.3
1978	0.4
1979	0.4
1980	0.4
1981	0.4
1982	0.4
1983	0.5
1984	0.5
1985	0.5
1986	0.5
1987	0.6
1988	0.6
1989	0.6
1990	0.6
1991	0.7
1992	0.7
1993	0.7
1994	0.8
1995	0.8
1996	0.8
1997	0.9
1998	0.9
1999	1
2000	1
2001	1
2002	1.1
2003	1.1
2004	1.2
2005	1.2
2006	1.3
2007	1.4
2008	1.4
2009	1.5