Year	US Dollars adjusted for inflation)
1970	12020
1971	12140
1972	12260
1973	13050
1974	12730
1975	12120
1976	12400
1977	12930
1978	13930
1979	14230
1980	15320
1981	15320
1982	14920
1983	14670
1984	14250
1985	13710
1986	12540
1987	12770
1988	12700
1989	13450
1990	13710
1991	13780
1992	14180
1993	14770
1994	15480
1995	15350
1996	15130
1997	15070
1998	14860
1999	14560
2000	14010
2001	14070
2002	14020
2003	14080