Year	Percent
1976	0.00193
1977	0.03581
1978	0.02502
1979	0.05045
1981	0.06172
1982	0.06594
1983	0.01376
1984	0.05606
1985	0.0096
1986	0.01323
1987	0.02471
1988	0.05991
1989	0.02275
1990	0.02265
1991	0.33118
1992	0.86545
1993	0.88077
1994	1.59748
1995	1.02387
1996	1.45241
1997	1.72178
1998	1.81849
1999	3.40268
2000	5.12021
2001	2.26787
2002	0.49207
2003	2.12345
2004	1.57556
2005	1.77507
2006	1.40286
2007	1.48199
2008	4.47632
2009	4.19567
2010	4.3291
2011	8.02846
2012	7.69539
2013	3.55205
2014	4.91215
2015	6.56756
2016	2.98543
2017	1.74107