Year	Percent
1961	8.63361
1962	5.80872
1963	4.51562
1964	6.37447
1965	14.17848
1966	8.33338
1967	8.69142
1968	11.77224
1969	13.26559
1970	8.20455
1971	11.42204
1972	11.39833
1973	5.6477
1974	3.54431
1975	-5.23685
1976	13.73371
1977	-7.02185
1978	-16.82831
1979	-13.58874
1980	-30.17957
1981	-8.82919
1982	22.15125
1983	4.18033
1984	-12.4551
1985	-1.87839
1986	-13.69566
1987	-3.16656
1988	-8.74386
1989	2.72764
1990	10.90004
1991	10.13202
1992	1.27236
1993	-0.21117
1994	-2.72182
1995	0.84655
1996	3.45274
1997	-1.32451
1998	0.27488
1999	-0.94584
2000	4.14659
2001	-0.67013
2002	5.86616
2003	7.42403
2004	3.16852
2005	2.01065
2006	3.81154
2007	6.94972
2008	-0.86998
2009	-0.14682
2010	4.54945
2011	1.38926
2012	-8.60915
2013	-1.45952
2014	3.30179
2015	-2.50115
2016	12.101
2017	3.16226