Year	Measure
1998	3.5
1999	3.5
2000	3.4
2001	2.6
2002	2.6
2003	2.5
2004	2.6
2005	2.6
2006	2.6
2007	2.6
2008	2.8
2009	3
2010	3
2011	3.19524