Year	Measure
2000	0.684
2001	0.681
2002	0.684
2003	0.686
2004	0.689
2005	0.694
2006	0.707
2007	0.71
2008	0.717
2009	0.724
2010	0.733
2011	0.735
2012	0.734
2013	0.723
2014	0.735
2015	0.735