Year	constant 2015 US$
1960	-380000
1963	140000
1964	500000
1965	550000
1966	370000
1967	4150000
1968	400000
1969	510000
1970	490000
1971	1510000
1972	6890000
1973	2150000
1974	2090000
1975	2360000
1976	2040000
1977	1460000
1978	3260000
1979	2940000
1980	4380000
1981	4380000
1982	4380000
1983	2120000
1984	23010000
1985	1690000
1986	10950000
1987	1140000
1988	6640000
1989	6530000
1990	4460000
1991	3780000
1992	3480000
1993	1350000
1994	1090000
1995	5240000
1996	2010000
1997	4630000
1998	29470000
1999	15590000
2000	7430000
2001	11220000
2002	6570000
2003	5260000
2004	6280000