Year	Percent
1976	0.92531
1977	0.941
1981	1.50794
1982	1.62772
1983	1.38599
1984	1.05973
1985	0.89106
1986	0.85393
1987	0.77045
1988	0.80799
1989	0.92926
1990	0.84079
1991	0.75852
1992	1.10784
1993	0.82191
1994	0.62992
1995	0.53871
1996	0.56766
1997	0.65505
1998	0.54495
1999	0.51105
2000	0.48632
2001	0.50436
2002	0.58543
2003	0.5816
2004	0.53597
2005	0.52766
2006	0.60892
2007	0.65246
2008	0.95336
2009	0.94721
2010	0.87421
2011	0.92545
2012	0.92982
2013	0.8996
2014	0.87289
2015	0.86842
2016	0.95917
2017	0.90354