Year	Percent
1985	35.67839
1986	33.38954
1987	32.41935
1988	32.26744
1989	29.27536
1990	24.82853
1991	22.92899
1992	33.44668
1993	39.15792
1994	36.54373
1995	28.66936
1996	22.31524
1997	19.68308
1998	15.42541
1999	17.33559
2000	7.42125
2001	8.98272
2002	6.29577
2003	8.04363
2004	10.37748
2005	11.6477
2006	15.96636
2007	24.633
2008	26.50873
2009	24.84475
2010	23.84618
2011	29.20944
2012	23.26736
2013	24.7353
2014	26.16039
2015	28.87074
2016	31.12127