Year	Percent
1961	6.09948
1962	21.24077
1963	87.8492
1964	3.54798
1965	38.95212
1966	4.97382
1967	58.57441
1968	59.88278
1969	17.73106
1970	-2.83695
1971	8.2037
1972	10.1814
1973	17.88705
1974	18.23832
1975	12.26542
1976	57.39543
1977	37.27165
1978	28.4143
1979	101.77004
1980	51.40755
1981	33.23022
1982	43.48528
1983	78.21547
1984	89.60322
1985	25.81091
1986	28.45326
1987	73.7674
1988	91.58619
1989	110.26225
1990	108.95531
1991	2338.44967
1992	3855.30764
1993	1657.64159
1994	26765.85825
1995	466.40736
1996	638.18882
1997	192.64283
1998	26.93538
1999	441.90249
2000	2630.12267
2001	73.05971
2002	31.71946
2003	13.41545
2004	6.36546
2005	29.86955
2006	13.32523
2007	20.27146
2008	20.46532
2009	32.65793
2010	20.78633
2011	13.79166
2012	5.93999
2013	2.77129
2014	0.99363
2015	-1.1559
2016	4.34925
2017	41.68645