Year	Percent
1990	4.83851
1991	5.00824
1992	5.54792
1993	8.01514
1994	8.12644
1995	8.05436
1996	8.17179
1997	8.69009
1998	9.03053
1999	9.07612
2000	9.6226
2001	9.3249
2002	9.81896
2003	12.51878
2004	13.10078
2005	13.10318
2006	12.87889
2007	12.44827
2008	13.31785
2009	12.38304
2010	12.85304
2011	12.66363
2012	12.95284
2013	12.4529
2014	12.61097
2015	12.33651
2016	12.15551