Year US Dollars adjusted for inflation) 1979 4809 1980 4650 1981 4214 1982 4086 1983 3853 1984 4166 1985 3821 1986 4239 1987 4291 1988 4079 1989 3997 1990 3848 1991 2984 1992 3083 1993 3239 1994 2860 1995 3402 1996 3244 1997 3098 1998 3012 1999 4493 2000 4376 2001 4545 2002 4441 2003 4324