Year	Years
1990	77
1991	77
1992	77.3
1993	77.6
1994	77.8
1995	78
1996	78.3
1997	78.7
1998	79
1999	79.3
2000	79.6
2001	79.8
2002	80
2003	80.3
2004	80.8
2005	81.2
2006	81.2
2007	81.3
2008	81.4
2009	81.6
2010	81.9
2011	82
2012	82.1
2013	82.1