Year	Percent
1986	1.14685
1987	1.57425
1988	1.2782
1989	1.99245
1990	2.07138
1991	2.3279
1992	3.14593
1993	1.76129
1994	3.84234
1995	3.57731
1996	3.23845
1997	3.00336
1998	2.66205
1999	2.51003
2000	2.20981
2001	1.77481
2002	1.51962
2003	1.44752
2004	1.29674
2005	1.12758
2006	1.0431
2007	0.91461
2008	0.79822
2009	1.31313
2010	1.4931
2011	1.49779
2012	1.54794
2013	1.5759
2014	1.65677
2015	2.11269
2016	1.84393
2017	2.08721