Year	Percent
1961	-26.52764
1962	-6.3515
1963	7.62225
1964	15.469
1965	14.19789
1966	7.6084
1967	-8.1615
1968	-6.57145
1969	13.77934
1970	16.0504
1971	4.15918
1972	1.29011
1973	5.32729
1974	0.21801
1975	6.81644
1976	-3.08132
1977	6.114
1978	10.18229
1979	6.17422
1980	6.463
1981	3.8338
1982	7.34193
1983	9.24522
1984	13.63833
1985	11.90911
1986	7.33133
1987	9.91217
1988	9.4579
1989	2.6007
1990	2.39361
1991	7.81296
1992	12.82495
1993	12.56603
1994	11.78157
1995	9.75028
1996	8.78218
1997	8.11855
1998	6.80781
1999	6.73927
2000	7.64
2001	7.5558
2002	8.40192
2003	9.35236
2004	9.45918
2005	10.74255
2006	12.09184
2007	13.63634
2008	9.09387
2009	8.85703
2010	10.1031
2011	9.01285
2012	7.33203
2013	7.22694
2014	6.75578
2015	6.35838
2016	6.1238
2017	6.30397