Year current US$ 1960 2.6876302888837627 1961 2.4364708093021563 1962 25.29840118501315 1963 10.036588983174825 1964 7.556885458752279 1965 9.296177338466983 1966 8.520642621277972 1967 5.721425066930668 1968 12.273236711695485 1969 16.926136275708384 1970 13.190961989081389 1971 19.776952311008923 1972 15.440266678858826 1973 26.14653490180998 1974 26.22303597671483 1975 33.62255317842808 1976 39.48128789361889 1977 38.34543858177991 1978 42.89362429099902 1979 48.83447495300647 1980 55.64846510123584 1981 60.79045736253592 1982 51.745504255446576 1983 45.588696597620505 1984 42.96605173467936 1985 43.108841038009736 1986 56.095807016705 1987 47.02045062053583 1988 68.40927942688397 1989 52.452166391395544 1990 63.06779752277987 1991 57.09502335951006 1992 79.73474495235715 1993 75.8238112014829 1994 49.45605999262977 1995 54.023623012373044 1996 58.74170587659007 1997 55.321336464024604 1998 45.32236053409915 1999 42.74843368642021 2000 35.27889889386589 2001 31.11776768075857 2002 40.205153565510514 2003 59.710639329097084 2004 75.60915245668818 2005 75.52664843769647 2006 63.187717617778276 2007 57.126946973568906 2008 50.271488139759526 2009 73.67567799937363 2010 83.785454802242 2011 82.99618474016039 2012 115.6566180089127 2013 99.86282952784993 2014 102.93153683403546 2015 111.73135996176843 2016 127.8568227534896 2017 158.7562323482801 2018 131.63278319024565 2019 140.1142149580071 2020 210.52300387481068 2021 659.0562454626145 2022 385.09688221871846