Year	%
1991	8.25
1995	5.75
1996	25.64
1997	17.09
1998	19.14
1999	12.34
2000	19.45
2001	20.77
2002	6.72
2003	21.52
2004	1.97
2005	2.18
2006	1.78
2007	1.93
2008	0.95
2009	1.12
2010	10.31
2011	9.93
2012	11
2013	9.95
2014	0.67
2015	8.06
2016	6.91
2017	0.66
2018	0.56