Year	Measure
1999	0.382
2000	0.391
2001	0.401
2002	0.406
2003	0.415
2004	0.426
2005	0.439
2006	0.454
2007	0.468
2008	0.48
2009	0.488
2010	0.495
2011	0.508
2012	0.523
2013	0.527
2014	0.531
2015	0.533