Year	Percent
1960	5.03905
1961	7.81508
1962	4.3722
1963	15.12665
1964	4.6814
1965	8.52757
1966	8.06853
1967	8.06123
1968	14.5162
1969	9.76242
1970	6.89217
1971	12.8038
1972	8.943
1973	11.2896
1974	8.18694
1975	6.36331
1976	3.14168
1977	-1.81427
1978	4.14237
1979	1.47132
1980	4.67985
1981	1.31867
1982	1.26735
1983	1.28282
1984	1.20945
1985	1.07261
1986	0.95164
1987	0.88835
1988	0.8427
1989	0.83907
1990	3.56772
1991	1.49059
1992	1.50916
1993	1.43112
1994	1.27736
1995	1.02257
1996	0.78659
1997	0.74308
1998	0.64332
1999	0.51049
2000	0.42641
2001	0.16093
2002	0.20228
2003	0.22757
2004	0.18859
2005	0.20497
2006	0.13379
2007	0.17484
2008	0.25288
2009	0.19657
2010	0.14156
2011	0.11603
2012	0.07306
2013	0.02239
2014	0.00292
2015	-0.0185
2016	-0.0487
2017	-0.09746