Year	Measure
1990	0.698
1991	0.707
1992	0.712
1993	0.715
1994	0.718
1995	0.722
1996	0.727
1997	0.731
1998	0.736
1999	0.737
2000	0.742
2001	0.745
2002	0.747
2003	0.754
2004	0.761
2005	0.767
2006	0.773
2007	0.779
2008	0.787
2009	0.792
2010	0.804
2011	0.818
2012	0.83
2013	0.841
2014	0.845
2015	0.847