Year current US$ 1970 7591312.72371533 1971 7747707.41681701 1972 7687603.44538647 1973 12619574.631645 1974 13307286.5842041 1975 18866268.0885199 1976 20080746.9088029 1977 23666548.1256371 1978 20396543.1045824 1979 26736286.1943672 1980 31690756.9674312 1981 24906436.6438728 1982 24145708.9567859 1983 23245433.6898573 1984 19059167.5070362 1985 19855166.9545414 1986 28116401.0473411 1987 24042540.9777166 1988 33334674.9871297 1989 32632009.7210132 1990 32042219.4698456 1991 28168396.8291112 1992 23389398.4813219 1993 21140650.0651293 1994 21370782.7248834 1995 23691785.9960964 1996 27322659.7910847 1997 18162714.6864909 1998 13907442.0410655 1999 18620478.8376951 2000 17422180.4251618 2001 15385880.995637 2002 15162601.704239 2003 21253454.6143944 2004 17224101.6044847 2005 17567811.8964914 2006 20308049.6249571 2007 28469748.6836188 2008 31860207.315387 2009 20470880.8844813 2010 20747252.8234044 2011 22495321.8267461 2012 26028743.5728628 2013 30165922.935872 2014 30191477.8921723 2015 24159906.1700255 2016 24082752.531689 2017 28138353.2566317 2018 27680303.2717587 2019 19615899.4117248 2020 17125276.6153085 2021 18428624.9868798