Year	Percent
1970	2.17697
1971	2.5452
1972	2.02777
1973	0.23113
1974	1.50002
1975	0.46845
1976	0.99404
1977	1.03393
1978	1.41797
1979	1.1051
1980	1.24873
1981	1.32887
1982	1.21985
1983	1.68665
1984	0.19389
1985	1.14467
1986	2.93223
1987	2.78432
1988	3.1298
1989	2.42532
1990	2.60936
1991	1.32542
1992	1.75424
1993	1.38618
1994	1.55205
1995	3.27502
1996	1.54418
1997	1.75606
1998	1.49334
1999	0.85249
2000	3.58837
2001	2.83361
2002	3.71529
2003	1.92695
2004	7.01215
2005	-3.62282
2006	4.09795
2007	5.2162
2008	4.29039
2009	3.09605
2010	3.07716
2011	4.7017
2012	3.72878
2013	3.43124
2014	3.13858
2015	2.7738
2016	3.30853
2017	3.40787