Year	Measure
1997	4.14
1998	4.3
1999	4.4
2001	5.1
2002	5.1
2003	5.5
2004	6.2
2005	5.9
2006	6.4
2007	6.7
2008	6.9
2009	6.7
2010	6.9
2011	7.04446