Year	Measure
2000	0.456
2001	0.462
2002	0.457
2003	0.466
2004	0.473
2005	0.478
2006	0.483
2007	0.491
2008	0.5
2009	0.503
2010	0.504
2011	0.506
2012	0.508
2013	0.509
2014	0.511
2015	0.512