Year	Percent
1960	-0.29338
1961	1.5781
1962	3.30216
1963	4.47419
1964	4.93095
1965	4.87402
1966	4.78687
1967	4.68415
1968	4.20022
1969	3.30855
1970	2.19828
1971	1.02802
1972	0.01126
1973	-0.7343
1974	-1.08423
1975	-1.09321
1976	-1.05802
1977	-1.00467
1978	-0.63447
1979	0.1194
1980	1.11446
1981	2.20508
1982	3.1508
1983	3.81838
1984	4.12674
1985	4.17215
1986	4.17698
1987	4.17246
1988	4.00656
1989	3.67873
1990	3.26075
1991	2.81773
1992	2.42813
1993	2.15236
1994	2.03534
1995	2.02352
1996	2.02278
1997	2.01156
1998	2.03926
1999	2.11658
2000	2.21488
2001	2.33297
2002	2.43874
2003	2.47548
2004	2.42734
2005	2.32838
2006	2.20549
2007	2.1067
2008	2.06751
2009	2.10942
2010	2.19461
2011	2.29574
2012	2.35485
2013	2.33853
2014	2.22227
2015	2.04441
2016	1.85067
2017	1.68461