Year	Percent
1961	2.56507
1962	4.51662
1963	5.23272
1964	65.88503
1965	51.56812
1966	116.86974
1967	40.63242
1968	48.31382
1969	35.16956
1970	21.73087
1971	37.5766
1972	22.10907
1973	142.92768
1974	195.88613
1975	67.61885
1976	123.72324
1977	112.28005
1978	189.84672
1979	138.1196
1980	91.07968
1981	94.99842
1982	70.80554
1983	83.5572
1984	94.13564
1985	104.42148
1986	93.38666
1987	72.87256
1988	66.09856
1989	133.15315
1990	112.34157
1991	69.62561
1992	63.85411
1993	182.68439
1994	40.30617
1995	77.30199
1996	103.69231
1997	109.06821
1998	83.5971
1999	100.65691
2000	111.25254
2001	129.45545
2002	214.30574
2003	59.21805
2004	23.38535
2005	13.14882
2006	21.22624
2007	28.51965
2008	26.45417
2009	30.16988
2010	20.58033
2011	14.59861
2012	12.38767
2013	8.58023
2014	9.46156
2015	13.89032
2016	15.35393
2017	11.31978
2018	12.91768
2019	12.39615
2020	20.19382
2021	11.34116