Year	Percent
1961	4.80889
1962	5.34937
1963	6.41669
1964	2.35244
1965	3.92451
1966	6.31199
1967	5.92343
1968	4.61156
1969	6.87632
1970	8.6445
1971	16.90209
1972	10.97568
1973	21.93022
1974	28.99235
1975	21.30924
1976	15.61266
1977	24.08902
1978	47.54115
1979	76.72087
1980	93.00322
1981	44.05707
1982	28.22683
1983	26.25825
1984	48.23683
1985	53.05448
1986	36.00689
1987	33.61223
1988	69.01813
1989	75.40483
1990	58.2444
1991	59.16411
1992	65.19944
1993	68.37943
1994	104.74914
1995	86.00754
1996	77.22351
1997	81.45486
1998	143.69254
1999	54.29047
2000	49.34068
2001	52.92366
2002	37.57443
2003	23.32004
2004	12.44689
2005	7.10486
2006	9.3717
2007	6.21664
2008	12.03734
2009	5.4018
2010	7.01266
2011	8.18857
2012	7.41822
2013	6.26881
2014	7.42168
2015	7.82694
2016	8.09826
2017	10.80867