Year	Percent
1986	0.4398
1987	0.9541
1988	0.9855
1994	1.4729
1997	0.5573
2001	0.4506
2005	0.2589
2007	0.34
2008	0.2552
2009	0.3652
2010	0.2903
2011	0.6426
2012	1.3423
2013	1.3526
2014	1.6953
2015	2.2801
2016	1.7604
2017	2.6481