Year	Percent
1961	3.83003
1962	4.03486
1963	3.20198
1964	3.99116
1965	2.90969
1966	3.32939
1967	2.82271
1968	7.23248
1969	11.56925
1970	13.42329
1971	21.78686
1972	22.24602
1973	17.25028
1974	5.02818
1975	4.54025
1976	6.51804
1977	7.73325
1978	9.93752
1979	7.89361
1980	7.84907
1981	5.15357
1982	8.25685
1983	9.32111
1984	4.98598
1985	3.71795
1986	4.84911
1987	8.56312
1988	16.00874
1989	9.86872
1990	3.80593
1991	4.5143
1992	0.15284
1993	-0.73357
1994	1.06335
1995	4.5426
1996	3.52288
1997	5.81178
1998	-1.20784
1999	7.71649
2000	0.30724
2001	-1.26866
2002	4.57868
2003	3.21186
2004	1.30273
2005	3.06243
2006	6.73137
2007	6.57005
2008	4.50209
2009	-9.2163
2010	6.67865
2011	4.16277
2012	2.55754
2013	9.29327
2014	2.22502
2015	-3.50557
2016	2.41195
2017	0.50998