Year	%
1988	0.9433649
1989	2.268005
1990	6.090529
1991	0
1992	0
1993	0.1481843
1994	0.0055281
1995	0.7070779
1996	0.5590848
1997	0.4018707
1998	0.7131561
1999	0.8353086
2000	1.697284
2001	0.9687108
2002	0.4574802
2003	0.3639411
2004	0.4206193
2005	0.4509256
2006	0.5785966
2007	0.4511918
2008	0.3889008
2009	0.4256028
2010	0.1943219
2011	0.2691756
2012	0.2977323
2013	0.7656891
2014	0.0081808
2015	1.043876
2016	1.034654
2017	0.6008491