Year	Percent
1986	6.61
1987	6
1992	4.77
1996	4.97
2001	8.5
2002	9.046
2003	7.705
2004	7.713
2005	6.287
2007	6.349
2008	6.208
2009	7.49
2010	6.7887
2011	5.888
2012	5.7632
2013	5.1469
2014	5.1593
2015	5.145
2016	5.679
2017	5.13