Year	Years
1980	-2.414
1981	-3.695
1982	-4.849
1983	-6.714
1984	-7.968
1985	-6.989
1986	-7.024
1987	-6.921
1988	-7.119
1989	-6.668
1990	-5.826
1991	-5.901
1992	-4.354
1993	-3.759
1994	-3.58
1995	-2.824
1996	-2.902
1997	-0.693
1998	0.6711
1999	0.8924
2000	1.162
2001	1.647
2002	1.613
2003	3.029