Year	Percent
1985	39.15099
1986	40.21063
1987	42.44583
1988	32.95247
1989	35.37063
1990	46.07962
1991	33.45019
1992	31.3784
1993	31.70178
1994	28.94183
1995	31.09
1996	28.40877
1997	27.0143
1998	33.00678
1999	39.10038
2000	36.69106
2001	39.61849
2002	44.72825
2003	46.46821
2004	41.20726
2005	33.75434
2006	30.85121
2007	31.5201
2008	27.75694
2009	35.77812
2010	40.28908
2011	43.71813
2012	40.82037
2013	43.2862
2014	43.41424
2015	39.79334
2016	40.42258