Year	Percent
1960	2.98328
1961	16.52855
1962	18.81467
1963	15.45498
1964	12.77492
1965	11.17979
1966	10.23808
1967	7.9107
1968	6.22212
1969	5.68414
1970	3.61824
1971	1.65275
1972	2.51435
1973	2.76387
1974	0.42273
1975	10.60293
1976	0.74258
1977	0.50166
1978	0.1243
1979	-0.73137
1980	-0.11764
1981	0.0068
1982	-0.03583
1983	0.34459
1984	0.30409
1985	1.63476
1986	0.10461
1987	0.58061
1988	0.86145
1989	0.88971
1990	1.26923
1991	1.40048
1992	1.18069
1993	1.2883
1994	1.0582
1995	0.79096
1996	0.83724
1997	0.51063
1998	0.4584
1999	0.41764
2000	0.27163
2001	0.32395
2002	-0.04174
2003	0.44881
2004	0.25709
2005	0.60007
2006	0.28973
2007	0.27565
2008	0.19802
2009	0.19293
2010	0.33828
2011	0.24065
2012	0.1666
2013	0.10562
2014	0.37608
2015	0.08754
2016	0.30184
2017	0.11247