Year	Years
1980	-2.405
1981	-0.6307
1982	0.1289
1983	1.26
1984	2.463
1985	3.472
1986	3.758
1987	4.04
1988	3.929
1989	4.681
1990	6.046
1991	3.584
1992	4.127
1993	3.728
1994	3.658
1995	3.372
1996	2.796
1997	2.497
1998	2.919
1999	3.742
2000	2.859
2001	2.337
2002	1.288
2003	0.6942