Year	Percent
1971	-0.33961
1972	-0.02463
1973	1.26646
1974	-0.05914
1975	10.52678
1976	5.88247
1977	4.76182
1978	4.12391
1979	2.29017
1980	1.42852
1981	0.1227
1982	0.54645
1983	0.24155
1984	0.77639
1985	0.2907
1986	1.47139
1987	4.39332
1988	0.54095
1989	3.49075
1990	3.451
1991	4.53038
1992	3.74177
1993	5.6874
1994	0.45107
1995	0.39009
1996	1.05181
1997	5.96421
1998	1.86865
1999	2.05313
2000	0.46066
2001	-2.1518
2002	0.04267
2003	-0.30335
2004	-0.71183
2005	0.13243
2006	9.70156
2007	16.66107
2008	12.35868
2009	8.12746
2010	24.35889
2011	12.87118
2012	2.24476
2013	4.72959
2014	1.79328
2015	2.79069
2016	3.02942
2017	2.80528