Year	Years
1990	66.7
1991	66.2
1992	65.5
1993	64.7
1994	63.9
1995	63.3
1996	63.1
1997	63
1998	63.1
1999	63.4
2000	63.6
2001	63.9
2002	64.1
2003	64.3
2004	64.5
2005	64.7
2006	65.1
2007	65.5
2008	66.1
2009	66.6
2010	67.1
2011	67.4
2012	67.6
2013	67.8