Year current US$ 1970 30230000.007897634 1971 36879999.84435737 1972 39699999.82975421 1973 40449999.92474913 1974 38120000.30651688 1975 56570000.07666647 1976 47589999.8471141 1977 37690000.070258975 1978 58850000.634789474 1979 64109999.91931024 1980 95189999.083057 1981 97289999.75323674 1982 89279999.74228437 1983 85780000.06824735 1984 73540000.40888788 1985 78410000.65207478 1986 91650000.13820836 1987 101589999.00147314 1988 131169999.93659553 1989 137229998.9890308 1990 134160000.80853704 1991 119429998.62693246 1992 103059999.18468295 1993 80809999.72857527 1994 76000000.62026082 1995 67690000.81159179 1996 71160001.14567578 1997 88440000.17642972 1998 73550000.08642672 1999 68820000.47340986 2000 53899999.499320984 2001 43480000.30592083 2002 27809999.652206905 2003 36060000.56117774 2004 55129999.77171422 2005 50060000.434517875 2006 54599999.69974161 2007 52939999.5803833 2008 54279999.72365795 2009 53240000.05424023 2010 55379999.9207258 2011 45339999.776333585 2012 41802485.50139366 2013 39347749.59459901 2014 35508877.728134386 2015 30404878.91901283 2016 25460085.846483696 2017 21510846.503078934 2018 13519442.1261549 2019 14331071.011722088 2020 17178486.09387875 2021 20389504.30974365 2022 21094721.555709835