Year	%
1988	3.407811
1989	2.966679
1990	1.090168
1991	1.349063
1992	0.8239979
1993	0.8126054
1994	0.9117332
1995	0.8981037
1996	0.475083
1997	0.6968602
1998	0.7358176
1999	0.9837306
2000	0.5727146
2001	0.5102799
2002	0.8133334
2003	0.564966
2004	1.064175
2005	0.5018089
2006	0.2620673
2007	0.645404
2008	0.5562064
2009	0.5388827
2010	0.4767331
2011	7.089327
2012	0.2564374
2013	7.161921
2014	0.0887031
2015	0.310075
2016	0.2430103
2017	0.1783994