Year	Years
1980	-2.047
1981	-3.022
1982	-4.348
1983	-4.323
1984	-4.241
1985	-3.563
1986	-2.055
1987	-1.951
1988	-2.018
1989	-2.724
1990	-1.684
1991	-2.061
1992	-2.891
1993	-5.515
1994	-5.473
1995	-6.3
1996	-6.787
1997	-6.69
1998	-6.649
1999	-7.417
2000	-9.493
2001	-8.981
2002	-6.948
2003	-2.489
2004	-2.598