Year	Percent
1960	50.88706
1961	50.7179
1962	46.91413
1963	47.76496
1964	46.5281
1968	42.25137
1969	41.98634
1970	41.2894
1971	47.60246
1972	44.07066
1973	55.48882
1974	77.90384
1975	92.95972
1976	71.7664
1977	68.29272
1978	64.27836
1979	75.78975
1980	75.31033
1981	81.36632
1982	74.61854
1983	54.0731
1984	47.04021
1985	47.17823
1986	40.73401
1987	33.60723
1988	34.47511
1989	40.88885
1990	11.1404
2004	106.78198
2005	94.5433
2006	77.14561
2007	70.67072
2008	71.62881
2009	71.97298
2010	69.59297
2011	70.54053
2012	69.09386
2013	63.53801
2014	58.67631
2015	49.23619
2016	48.1681
2017	43.87458