Year	Percent
1984	4.19442
1985	1.63228
1986	1.6528
1987	2.90636
1988	4.23787
1989	4.72978
1990	5.05872
1991	5.16994
1992	4.60837
1993	3.6395
1994	3.18666
1995	3.46308
1996	6.06653
1997	9.47893
1998	9.58659
1999	12.04535
2000	13.22386
2001	21.30602
2002	22.68189
2003	24.12225
2004	25.63311
2005	25.10391
2006	43.56062
2007	50.00676
2008	47.58872
2009	52.70269
2010	54.83472
2011	55.74995
2012	53.95292
2013	42.47225
2014	37.12023
2015	25.82229
2016	21.2087