Year	Years
1990	69.4
1991	69.7
1992	70
1993	70.3
1994	70.8
1995	71.2
1996	71.8
1997	72.3
1998	73
1999	73.6
2000	74.3
2001	74.7
2002	75.2
2003	75.6
2004	75.9
2005	76.2
2006	76.5
2007	76.6
2008	76.8
2009	76.7
2010	76.8
2011	76.8
2012	76.9
2013	77.1