Year	Years
1990	78.2
1991	78.3
1992	78.3
1993	78.2
1994	78.1
1995	78.2
1996	78.3
1997	78.4
1998	78.6
1999	78.8
2000	79.1
2001	79.5
2002	79.8
2003	80
2004	80.2
2005	80.4
2006	80.7
2007	80.9
2008	81.1
2009	81.4
2010	81.6
2011	81.9
2012	82
2013	82.2