Year current US$ 1971 96.59552330662214 1972 116.80649392014213 1973 138.0920426676595 1974 149.23384704258777 1975 174.33460967287448 1976 175.5015855832798 1977 175.0821225608464 1978 215.19774723516775 1979 277.02860149755895 1980 317.95843703434247 1981 286.30248963455165 1982 258.26357987718234 1983 218.0490500393839 1984 199.6361082771774 1985 200.55628029052605 1986 246.55815247347732 1987 280.87614924899765 1988 283.02134930115426 1989 245.54009363680595 1990 312.6392925481789 1991 308.02416805734543 1992 238.58045905781256 1993 320.4162697002601 1994 198.80230060143896 1995 261.8988362217186 1996 276.602611457736 1997 262.72143600101833 1998 279.8799567238669 1999 434.25742223068147 2000 407.32009208240237 2001 422.044005513137 2002 478.63385738956987 2003 597.6837676521359 2004 674.3484371900173 2005 698.7448127069696 2006 725.5337290875941 2007 820.4914420225524 2008 955.8068696588076 2009 915.4088118659279 2010 866.930513953977 2011 954.0628106289319 2012 974.4254972228867 2013 1079.2872642120806 2014 1117.7821306006945 2015 933.9750394492966 2016 941.6727486138071 2017 973.6613921174663 2018 1060.9516409656383 2019 1038.1853790985501 2020 1093.8858011958675 2021 1210.8868870626022