Year	Years
1970	4.335
1971	3.41
1972	4.382
1973	4.186
1974	3.787
1975	3.011
1976	1.417
1977	-0.3251
1978	-0.7912
1979	-0.1923
1980	-0.8356
1981	-0.1773
1982	-0.2224
1983	1.732
1984	1.827
1985	3.935
1986	3.881
1987	3.777
1988	4.442
1989	4.437
1990	4.019
1991	3.661
1992	3.474
1993	2.959
1994	2.24
1995	2.525
1996	2.454
1997	3.526
1998	3.597
1999	4.224
2000	5.705
2001	5.033
2002	5.231
2003	4.895