Year constant 2015 US$ 1970 15984.408815153522 1971 16641.185159266603 1972 17605.196938018085 1973 18555.779892731443 1974 18902.862568603025 1975 18958.68176132628 1976 19841.844419088142 1977 20757.04168070027 1978 20856.332335355997 1979 21940.552018838178 1980 22114.689930715893 1981 21881.209701316944 1982 22288.18542333763 1983 23134.078438507902 1984 23172.95713632128 1985 23667.766712108336 1986 24300.46391680138 1987 24743.69269107334 1988 25674.741485048417 1989 26538.273679010945 1990 27517.0923033083 1991 28044.498562407218 1992 28293.656331680744 1993 28041.966834663897 1994 28608.712368680615 1995 29179.749483054216 1996 29779.915805805384 1997 30168.918277014465 1998 31148.822855153794 1999 31684.121492828246 2000 32774.924613453615 2001 32725.794746373886 2002 33420.536109683315 2003 33563.10037618165 2004 34356.97711379986 2005 34750.639055476335 2006 36007.33783419495 2007 37111.24200160369 2008 37570.54860756386 2009 35576.914735992876 2010 36170.26775427931 2011 36601.78108869766 2012 36289.037813240975 2013 35989.48865808493 2014 36022.51560895799 2015 35811.6857751508 2016 36759.35375188633 2017 36633.63456724209 2018 37218.91789942956 2019 37611.485331974225 2020 34985.108141949655 2021 36098.250885241294