Year current US$ 1970 5230516.49196001 1971 5419109.08992 1972 6355985.14285714 1973 7103581.33606577 1974 7734279.36507937 1975 9071514.92063491 1976 10054453.3333333 1977 13140268.63092 1978 15489904.4444445 1979 19308416.6666667 1980 22548725.75808 1981 28984400 1982 26840125.988889 1983 28656236.6681723 1984 22404720.5747222 1985 26026894.5231584 1986 33070263.6419375 1987 33091534.4771772 1988 33902973.7526266 1989 35935669.001669 1990 36867988.0879391 1991 39309220.8271583 1992 38497668.5866262 1993 37729419.6831076 1994 41114474.5431662 1995 46436858.6375612 1996 34205019.6928158 1997 38226074.4932844 1998 33947921.791365 1999 25895113.1818263 2000 26676299.8863765 2001 24032464.9875354 2002 22565512.3719473 2003 21485250.1051222 2004 25172844.7455601 2005 39575748.0834472 2006 49949727.0589316 2007 58063434.3488859 2008 74750218.2693837 2009 96340372.9960641 2010 128552600.625164 2011 127997735.547965 2012 132396954.188601 2013 126975792.988883 2014 139652247.718746 2015 160666821.370701 2016 136532982.586649 2017 140452900.637172 2018 137967190.587776 2019 133732062.511255 2020 137887116.735111 2021 144290531.041192