Year	Years
1990	67.9
1991	73.1
1992	73.3
1993	73.6
1994	73.9
1995	74.3
1996	74.7
1997	75.1
1998	75.5
1999	75.9
2000	76.2
2001	76.5
2002	76.7
2003	76.9
2004	77.1
2005	77.3
2006	76.8
2007	77.2
2008	77.6
2009	77.8
2010	78
2011	76.2
2012	78.2
2013	78.3