Year	US Dollars adjusted for inflation)
1970	4385
1971	4574
1972	4584
1973	4320
1974	3828
1975	3570
1976	3851
1977	3968
1978	4127
1979	3641
1980	3438
1981	4293
1982	4643
1983	4896
1984	4882
1985	5022
1986	5569
1987	5897
1988	6068
1989	5752
1990	6183
1991	6106
1992	6958
1993	7060
1994	6993
1995	6997
1996	7337
1997	7546
1998	8090
1999	8306
2000	8197
2001	7692
2002	7907
2003	7566