Year	Percent
1975	43.82892
1976	38.3154
1977	42.82018
1978	58.40941
1979	63.13762
1980	63.63793
1981	66.59236
1982	82.11843
1983	54.9154
1984	45.59471
1985	39.34408
1986	46.48179
1987	41.84984
1988	45.93393
1989	36.54208
1990	22.63837
1991	23.42503
1992	21.24076
1993	25.15824
1994	31.24184
1995	38.56566
1996	43.69481
1997	59.84654
1998	80.75591
1999	116.56388
2000	87.00461
2001	71.73722
2002	72.04847
2003	67.92178
2004	48.35622
2005	46.18652
2006	38.24855
2007	28.05209
2008	23.4713
2009	23.48895
2010	18.37047
2011	18.72678
2012	15.68821
2013	28.1201
2014	22.45096
2015	38.10197
2016	51.24553