Year	Years
1980	3.979
1981	3.472
1982	2.785
1983	2.416
1984	2.156
1985	1.927
1986	0.4311
1987	-0.1015
1988	-0.5029
1989	-1.83
1990	-2.878
1991	-2.9
1992	-2.647
1993	-1.805
1994	-2.84
1995	-1.677
1996	-1.593
1997	-1.181
1998	-1.116
1999	-0.05555
2000	0.5937