Year	Years
1990	68.7
1991	68.4
1992	68.3
1993	68.4
1994	69
1995	69.6
1996	70.1
1997	70.1
1998	69.8
1999	69.3
2000	68.8
2001	68.4
2002	68.2
2003	68.1
2004	68.3
2005	68.5
2006	68.7
2007	68.9
2008	69.1
2009	69.3
2010	69.5
2011	69.7
2012	69.9
2013	70.1