Year	Years
1970	2.545
1971	3.113
1972	2.566
1973	3.268
1974	2.771
1975	4.195
1976	6.167
1977	4.074
1978	5.34
1979	4.426
1980	5.956
1981	6.131
1982	4.266
1983	4.897
1984	2.97
1985	1.198
1986	-0.07029
1987	0.8848
1988	0.6036
1989	-1.539
1990	-2.218
1991	-2.439
1992	-2.149
1993	-1.768
1994	-1.029
1995	-0.1415
1996	1.369
1997	2.119
1998	1.473
1999	2.651
2000	2.797
2001	2.056
2002	1.823
2003	1.56