Year	constant 2015 US$
1974	11890000
1975	13480000
1976	16590000
1977	13800000
1978	9030000
1979	5960000
1980	6740000
1981	14350000
1982	22210000
1983	15830000
1984	17160000
1985	13710000
1986	18440000
1987	16960000
1988	12200000
1989	13690000
1990	15720000
1991	22240000
1992	18180000
1993	15160000
1994	21320000
1995	7110000
1996	5190000
1997	4950000
1998	7090000
1999	8970000
2000	8350000
2001	8770000
2002	5180000
2003	2490000
2004	3230000
2005	5240000
2006	-430000
2007	13800000