Year	Measure
1998	3.3
1999	3.3
2000	3.5
2001	3.4
2002	3.9
2003	3.3
2004	3.6
2005	3.5
2006	3.3
2007	3.7
2008	3.9
2009	3.9
2010	4.1
2011	3.85076