Year	Percent
1989	0.27452
1990	0.06637
1991	2.82106
1992	0.83668
1993	2.209
1994	1.20885
1995	2.1471
1996	2.78529
1997	4.63329
1998	4.70739
1999	6.94645
2000	5.21799
2001	2.82164
2002	3.90298
2003	3.78209
2004	4.31364
2005	3.81407
2006	4.2403
2007	5.14186
2008	7.38264
2009	5.22853
2010	5.59335
2011	9.57919
2012	7.28921
2013	7.42513
2014	7.44164
2015	7.53226
2016	6.8176
2017	6.49039