Year	Years
1961	1.925
1962	1.454
1963	1.444
1964	1.632
1965	1.517
1966	1.27
1967	1.379
1968	1.649
1969	1.389
1970	1.3
1971	1.507
1972	2.475
1973	4.362
1974	4.608
1975	5.071
1976	5.943
1977	6.207
1978	6.368
1979	6.595
1980	6.379
1981	6.439
1982	5.177
1983	2.626
1984	1.929
1985	1.495
1986	0.8109
1987	-0.7109
1988	-0.2341
1989	-0.8106
1990	-1.031
1991	-1.074
1992	-0.8837
1993	-0.4745
1994	-0.3896
1995	-0.3376
1996	-0.3296
1997	0.7458
1998	-0.2265
1999	-0.2405
2000	-0.3156
2001	-0.4119
2002	-0.4735
2003	-0.2999
2004	0.01158