Year	Percent
1976	11.09366
1977	12.54667
1978	19.80557
1979	45.61207
1980	34.16197
1981	46.90701
1982	78.72202
1983	29.88619
1984	37.97213
1985	33.21984
1986	43.41141
1987	34.21591
1988	40.07194
1989	35.86003
1990	33.21031
1991	32.36611
1992	26.21199
1993	24.15863
1994	21.34665
1995	30.77718
1996	26.5375
1997	33.83017
1998	38.1154
1999	44.6577
2000	35.52658
2001	38.17512
2002	42.48228
2003	33.84265
2004	43.95418
2005	37.07302
2006	30.70438
2007	23.88915
2008	11.64499
2009	49.81972
2010	9.0794
2011	9.64346
2012	9.90525
2013	11.26418
2014	13.7482
2015	23.23125
2016	26.77249