Year	Years
1970	8.144
1971	7.71
1972	8.38
1973	7.35
1974	7.452
1975	6.179
1976	10.64
1977	5.919
1978	1.911
1979	0.801
1980	0.8749
1981	-0.5416
1982	-1.997
1983	-2.839
1984	-3.93
1985	-3.752
1986	-7.508
1987	-5.258
1988	-1.899
1989	-1.691
1990	-1.863
1991	-0.6599
1992	-1.026
1993	-0.7868
1994	-0.3623
1995	-0.3934
1996	0.08389
1997	-0.0368
1998	-0.05422
1999	-1.014
2000	-2.205
2001	-2.755
2002	-2.839
2003	-2.996
2004	-3.802