Year	Years
1970	3.958
1971	4.322
1972	3.956
1973	2.813
1974	1.452
1975	3.126
1976	2.862
1977	2.682
1978	2.573
1979	2.439
1980	0.7678
1981	0.2374
1982	1.436
1983	1.12
1984	1.411
1985	0.7277
1986	0.7371
1987	0.6707
1988	-0.1893
1989	0.8792
1990	1.314
1991	0.6844
1992	-0.6044
1993	-0.5307
1994	-1.066
1995	-1.011
1996	-1.221
1997	-0.9816
1998	-0.6572
1999	-1.671
2000	-0.799
2001	-0.4683
2002	-0.5793
2003	-0.3054