Year US Dollars adjusted for inflation) 1950 1232 1951 1307 1952 1344 1953 1363 1954 1293 1955 1263 1956 1278 1957 1300 1958 1376 1959 1379 1960 1451 1961 1498 1962 1473 1963 1447 1964 1696 1965 1724 1966 1678 1967 1708 1968 1800 1969 1848 1970 1892 1971 1908 1972 1978 1973 1873 1974 1900 1975 1829 1976 2042 1977 2228 1978 2239 1979 2335 1980 2572 1981 2550 1982 2608 1983 2714 1984 2789 1985 2862 1986 2957 1987 3081 1988 3124 1989 3266 1990 3384 1991 3499 1992 3566 1993 3587 1994 3667 1995 3757 1996 4103 1997 4095 1998 4252 1999 4425 2000 4536 2001 4609 2002 4688 2003 4759