Year	Percent
1979	3.90395
1980	6.00297
1981	5.41959
1982	6.81142
1983	7.9774
1984	10.19606
1985	11.7154
1986	11.48188
1987	11.8092
1988	10.14046
1989	8.5016
1990	9.18047
1991	9.4729
1992	7.10317
1993	6.06325
1994	6.34643
1995	3.81281
1996	2.20136
1997	1.69373
1998	2.20765
1999	2.62109
2000	2.59341
2001	1.87082
2002	1.7979
2003	1.29905
2004	0.83072
2005	0.89237
2006	0.88633
2007	1.63896
2008	1.15189
2009	1.74823
2010	1.2483
2011	8.19771
2012	1.55176
2013	1.78287
2014	2.02577
2015	2.15643
2016	5.73218