Year US Dollars adjusted for inflation) 1950 329.3 1951 365.9 1952 370.4 1953 383.1 1954 376.3 1955 381.5 1956 393.1 1957 379.9 1958 373.7 1959 391.7 1960 399 1961 405.7 1962 409.4 1963 414.6 1964 427.5 1965 444.8 1966 450.9 1967 450.6 1968 464.5 1969 480.1 1970 478.7 1971 489.3 1972 497.4 1973 502.2 1974 500 1975 489.3 1976 496.1 1977 490.2 1978 480.1 1979 493.3 1980 505.3 1981 515.2 1982 504.4 1983 520.6 1984 465.9 1985 461.2 1986 463.7 1987 363.9 1988 462.9 1989 429 1990 463.8 1991 437.2 1992 552.3 1993 593.2 1994 595.6 1995 607.5 1996 645.6 1997 668.7 1998 668.7 1999 722.9 2000 725.4 2001 723.4 2002 737.7 2003 687.3