Year	Measure
1990	0.353
1991	0.361
1992	0.375
1993	0.381
1994	0.388
1995	0.393
1996	0.399
1997	0.405
1998	0.408
1999	0.417
2000	0.427
2001	0.435
2002	0.445
2003	0.455
2004	0.465
2005	0.474
2006	0.484
2007	0.493
2008	0.504
2009	0.515
2010	0.526
2011	0.533
2012	0.54
2013	0.547
2014	0.552
2015	0.556