Year	Percent
1962	16.77703
1963	28.31325
1964	24.17413
1965	9.06072
1966	12.97449
1967	9.70939
1968	14.43081
1969	15.87403
1970	-9.39223
1971	-3.0254
1972	-9.58813
1973	-15.21064
1974	-16.50282
1975	-7.83158
1976	-5.48546
1977	-5.6614
1980	-232.27389
1981	-302.18173
1982	-279.86879
1983	-129.81808
1984	-152.94071
1985	-73.40792
1986	-106.46716
1987	-150.97721
1988	-163.04359
1989	-133.73807
1990	-125.3639
1991	-162.82645
1992	-96.00617
1993	-83.2149
1994	-57.92869
1995	-217.92201
1996	-344.75077
1997	-166.58017
1998	-299.84251
1999	-164.83481
2000	-90.00656
2001	-102.31935
2002	-6.59909
2003	-69.28761
2004	-24.7599
2005	43.81029
2006	46.11852
2007	43.1588
2008	49.76069
2009	26.47234
2010	26.84864
2011	35.81328
2012	27.13456
2013	28.41335
2014	27.54738
2015	14.43889
2016	10.13273
2017	18.65693