Year	Years
1960	-0.5232
1961	0.42
1962	1.307
1963	3.049
1964	2.799
1965	4.427
1966	5.03
1967	4.617
1968	5.302
1969	4.936
1970	4.877
1971	5.245
1972	4.77
1973	4.864
1974	4.786
1975	4.665
1976	4.723
1977	5.035
1978	5.497
1979	5.07
1980	4.604
1981	4.673
1982	5.241
1983	4.621
1984	4.871
1985	5.075
1986	4.581
1987	4.309
1988	4.067
1989	5.049
1990	5.858
1991	5.941
1992	6.205
1993	6.872
1994	7.041
1995	7.009
1996	7.063
1997	6.31
1998	4.542
1999	3.983
2000	2.941
2001	2.481
2002	2.125
2003	2.079