Year	Measure
1997	6.45
1998	5.6
1999	5.1
2000	5.4
2001	4.5
2002	4.5
2003	4.3
2004	4.9
2005	4.2
2006	4.1
2007	5
2008	5.1
2009	5.3
2010	5.3
2011	4.79809