Year	Years
1990	75.1
1991	75.3
1992	75.4
1993	75.5
1994	75.5
1995	75.7
1996	75.9
1997	76.2
1998	76.5
1999	76.7
2000	76.9
2001	77.2
2002	77.4
2003	77.6
2004	77.9
2005	78.1
2006	78.3
2007	78.5
2008	78.7
2009	79
2010	79.3
2011	79.6
2012	79.8
2013	79.9