Year	Percent
1969	2.02064
1970	52.21159
1971	15.28551
1972	17.29927
1973	18.24873
1974	10.54389
1975	-13.45685
1976	11.94531
1977	1.72034
1978	-10.11428
1979	5.82602
1980	-0.43225
1981	-4.21352
1982	-25.61908
1983	-21.15914
1984	-10.16819
1985	-14.61044
1986	11.27646
1987	-10.85327
1988	8.41064
1989	-4.2965
1990	11.16566
1991	11.31915
1992	0.92991
1993	-4.01976
1994	-1.9199
1995	-2.05977
1996	0.51437
1997	-0.83477
1998	0.94297
1999	-5.71676
2000	3.23506
2001	-3.7115
2002	-5.49294
2003	8.03586
2004	4.8331
2005	2.58508
2006	-0.02466
2007	-0.87229
2008	3.431
2009	-4.70683
2010	2.11269
2011	6.8325
2012	2.337
2013	-0.2438
2014	0.84957
2015	1.53181
2016	-0.59282
2017	-2.73209