Year	Years
1960	1.766
1961	2.603
1962	3.169
1963	2.692
1964	2.358
1965	2.571
1966	2.581
1967	2.463
1968	3.037
1969	2.776
1970	2.743
1971	2.237
1972	1.973
1973	1.952
1974	1.773
1975	1.792
1976	1.659
1977	1.785
1978	1.288
1979	1.382
1980	1.611
1981	1.426
1982	1.281
1983	1.514
1984	1.681
1985	1.152
1986	0.6173
1987	0.4398
1988	0.6305
1989	0.6287
1990	0.2757
1991	0.1273
1992	-0.4159
1993	-0.6747
1994	-0.596
1995	-0.4181
1996	0.1576
1997	0.2834
1998	0.2027
1999	0.2939
2000	0.6325
2001	1.112
2002	1.747
2003	1.949
2004	2.263