Year	Percent
1960	6.78168
1961	6.91026
1962	-0.3155
1963	-5.25085
1964	-8.33658
1965	-3.96352
1966	-8.99482
1967	-6.92888
1968	-8.15494
1969	-7.63104
1970	-7.36502
1971	-8.1253
1972	-4.81055
1973	-3.80006
1974	-11.29683
1975	-2.30045
1976	-7.30121
1977	-4.16821
1978	-6.82808
1979	-6.35411
1980	-9.77228
1981	-4.19706
1982	-4.90959
1983	-3.89701
1984	-4.6368
1985	-8.95002
1986	-9.10486
1987	-11.86053
1988	-8.72658
1989	-11.0584
1990	-9.8648
1991	-2.93512
1992	-6.8573
1993	-5.22423
1994	-4.74083
1995	-3.44452
1996	-2.86907
1997	-3.78866
1998	-7.29153
1999	-6.34055
2000	-8.30474
2001	-6.72933
2002	-7.27526
2003	-0.14351
2004	0.94353
2005	-4.99128
2006	-7.31665
2007	-8.42319
2008	-13.57858
2009	-8.55043
2010	-10.64843
2011	-10.61572
2012	-9.22232
2013	-6.34744
2014	-5.2599
2015	-4.90473
2016	-3.99701
2017	-3.25827