Year	Percent
1990	4.663
1991	4.623
1992	5.402
1993	5.728
1994	5.035
1995	4.3623
1996	3.218
1997	2.8465
1998	2.0485
1999	1.8688
2000	2.646
2001	2.6583
2002	2.7856
2003	3.7929
2004	3.5483
2005	3.849
2006	3.0253
2007	1.8783
2008	2.011
2009	2.7797
2010	3.3667
2011	2.8631
2012	2.9266
2013	2.8641
2014	3.4151
2015	4.191
2016	4.8841
2017	3.9724