Year	Percent
1960	55.24079
1961	51.37933
1962	56.67447
1963	60.078
1964	59.7929
1965	82.02945
1966	80.51347
1967	75.40884
1968	64.92367
1969	82.92471
1970	86.1571
1971	98.51746
1972	101.54377
1973	102.80242
1974	99.70923
1975	100.77162
1976	101.87653
1977	104.49347
1978	102.21321
1979	120.58438
1980	112.54342
1981	111.18751
1982	112.62113
1983	116.86845
1984	109.36525
1985	117.33425
1986	113.09498
1987	128.42987
1988	100.62254
1989	108.85918
1990	98.40216
1991	96.27693
1992	86.89227
1993	85.35881
1994	82.59513
1995	85.67604
1996	86.01924
1997	101.58928
1998	89.94963
1999	88.28907
2000	82.16533
2001	78.67592
2002	78.50914
2003	69.99857
2004	75.2955
2005	76.38951
2006	75.19378
2007	84.47919
2008	92.84521
2009	79.70814
2010	80.94411
2011	83.8742
2012	95.30347
2013	109.03226
2014	102.08698
2015	94.11099
2016	86.26636
2017	63.39689