Year US Dollars adjusted for inflation) 1960 16354.54003 1961 16188.54185 1962 17051.76943 1963 17433.15465 1964 18624.89699 1965 19958.80876 1966 20240.00251 1967 21068.58249 1968 22188.72983 1969 23343.46173 1970 24369.03026 1971 25120.53664 1972 25746.60153 1973 26924.62419 1974 27633.08251 1975 27388.41417 1976 28385.22768 1977 28928.1338 1978 29525.88536 1979 29913.38466 1980 30075.85265 1981 29636.15785 1982 29134.53912 1983 29625.05368 1984 30411.12599 1985 31050.65216 1986 31739.39645 1987 32147.72856 1988 33039.84199 1989 34293.89214 1990 35483.2995 1991 36063.47085 1992 36402.47289 1993 36604.23348 1994 37461.56616 1995 38438.55384 1996 39626.29266 1997 41117.96329 1998 42714.51301 1999 44574.68846 2000 46133.17635 2001 46758.87675 2002 46509.51714 2003 46422.02485 2004 47200.42469 2005 48107.58549 2006 49720.39486 2007 51447.25959 2008 52118.09256 2009 49897.22517 2010 50338.25483 2011 50937.55294 2012 50212.96411 2013 49969.85027 2014 50497.2368 2015 51410.4893 2016 52267.73176 2017 53597.83433