1992	7.7
1993	8.9
1994	9.6
1995	9.4
1996	10.4
1997	11.4
1998	11.1
1999	10.5
2000	9.6
2001	9.4
2002	9.8
2003	10.5
2004	10.5
2005	11.7
2006	10.8
2007	9.0
2008	7.8
2009	8.1
2010	7.7
2011	7.1
2012	6.8
2013	6.9
