Year	US Dollars adjusted for inflation)
1970	1087
1971	1020
1972	953
1973	763.1
1974	713.2
1975	693.4
1976	684.3
1977	577
1978	571.3
1979	493.1
1980	458.2
1981	456.6
1982	434.5
1983	413.6
1984	399.5
1985	379.6
1986	356
1987	346.8
1988	397.8
1989	389.7
1990	388.4
1991	413
1992	435.8
1993	447.4
1994	468.6
1995	444.5
1996	462.9
1997	477.4
1998	471.6
1999	476.7
2000	513.9
2001	544.3
2002	561.5
2003	580