Year current US$ 1971 502.4367740865244 1972 553.9635002648567 1973 674.0450178771706 1974 720.2230213747507 1975 817.2210526013544 1976 980.9257705168292 1977 1228.628444595863 1978 1359.7320059648894 1979 1504.5818509474566 1980 1737.3300617481525 1981 853.1253170382746 1982 782.8304854571974 1983 990.8402793887624 1984 1158.4804852391997 1985 1225.7493632058374 1986 1365.6667608851697 1987 1358.6085675947747 1988 1335.2727750146212 1989 1475.9984589763171 1990 1624.4197642279894 1991 2033.319687581865 1992 2370.44141395833 1993 2594.465778754694 1994 2815.7858503910547 1995 3026.015081623049 1996 2991.5381971166507 1997 3156.3637986605413 1998 3315.651222347106 1999 3300.078203467344 2000 3378.3685165429024 2001 3530.749080404281 2002 3595.9461670787264 2003 3687.505220674138 2004 3925.154877178259 2005 4166.283600032971 2006 4715.918286512499 2007 5543.463394543582 2008 6322.827453771601 2009 6119.072887278395 2010 7417.777521461184 2011 8301.60488959396 2012 9109.07152132419 2013 9678.351105199836 2014 9736.609781113571 2015 10446.759040717312 2016 10786.888023346273 2017 10833.446519930527 2018 11041.918998774068 2019 11300.935194467927 2020 10790.542539272767 2021 10968.731374290666