Year	Percent
1976	0.93102
1978	0.93243
1979	0.93665
1980	0.92637
1981	0.92209
1982	0.93316
1983	0.95863
1984	0.94993
1985	0.93918
1986	0.93854
1987	0.94115
1988	0.95444
1989	0.95229
1990	0.9429
1991	0.9444
1992	1.00517
1993	1.03438
1994	0.99509
1995	0.97107
1996	0.9752
1997	0.95824
1999	0.95554
2000	0.96296
2001	0.97363
2004	0.96639
2005	0.96428
2006	0.97094
2007	0.98215
2008	0.98415
2009	1.00058
2010	0.98682
2011	0.97929
2012	0.9697
2013	0.95747
2014	0.9457
2015	0.94278
2016	0.94547