Year current US$ 1971 5343600.84065187 1972 4308750.79637005 1973 2007764.78670068 1974 3132249.13557634 1975 3101300.12569122 1976 3458363.27253914 1977 3886127.70840746 1978 4653207.01682159 1979 6421690.905931 1980 9026085.79796951 1981 9475888.96131576 1982 9371662.41052062 1983 8986133.88299268 1984 10642384.5708877 1985 10933506.2648101 1986 9652663.15682461 1987 9479244.16617894 1988 11046723.275847 1989 10912958.822066 1990 12623373.6651696 1991 14056767.4460322 1992 16956370.2529193 1993 19022908.8768478 1994 27634514.4168808 1995 36860221.7521296 1996 40872092.3117472 1997 41862974.6838014 1998 37284988.2840391 1999 40136472.1485349 2000 33427189.8700865 2001 34351122.7295009 2002 27399564.0861305 2003 31833090.7651695 2004 37339619.4563448 2005 41376754.894088 2006 47806989.6669933 2007 54994007.2792322 2008 62276896.5124967 2009 66658585.5221117 2010 77305792.9862469 2011 86716398.8187931 2012 95184391.6808268 2013 100105138.082222 2014 104477104.794526 2015 105490312.328803 2016 110212354.071977 2017 125135160.283077 2018 134850313.598665 2019 135527544.584838 2020 134301798.061853 2021 144039388.166228