Year	Percent
1961	2.64763
1962	4.76642
1963	3.3927
1964	4.72213
1965	4.77463
1966	3.97708
1967	2.96498
1968	4.42388
1969	4.19554
1970	13.62062
1971	6.38428
1972	5.5175
1973	8.68454
1974	11.37114
1975	8.88523
1976	7.84056
1977	8.16968
1978	6.26095
1979	5.70216
1980	13.12609
1981	12.87923
1982	10.50996
1983	6.9624
1984	6.21
1985	5.19801
1986	-0.55083
1987	7.22137
1988	4.86853
1989	5.61208
1990	3.81143
1991	2.2117
1992	-0.63971
1993	2.29267
1994	-0.15594
1995	3.06148
1996	4.2615
1997	2.78566
1998	-0.69026
1999	6.66523
2000	15.43445
2001	1.64062
2002	-1.69482
2003	2.86312
2004	5.83506
2005	8.75946
2006	8.77614
2007	3.05008
2008	10.43366
2009	-5.20503
2010	5.9528
2011	6.75105
2012	3.35718
2013	2.54452
2014	0.32981
2015	-2.82178
2016	-1.11407
2017	3.84549