Year constant 2015 US$ 1970 16245.978294375062 1971 16607.179780415478 1972 17284.038798151458 1973 18103.402776769 1974 17943.43867118052 1975 17761.131304442548 1976 18430.815517448093 1977 18933.779938213036 1978 19633.231170603125 1979 20025.182207837017 1980 19834.27372105654 1981 20040.25737364359 1982 19836.218173807196 1983 20190.192776412794 1984 21184.035378880177 1985 21737.786563445832 1986 22247.870892284103 1987 22911.346002427632 1988 23857.6006775643 1989 24408.101279206196 1990 24816.342424950002 1991 24868.466411929745 1992 25310.713620414637 1993 25526.758501400192 1994 26291.63765730352 1995 26860.345870684137 1996 27559.515686295344 1997 28367.91860658157 1998 29112.194612973995 1999 29894.937489497832 2000 30863.420784423586 2001 31153.480433818382 2002 31356.610448510473 2003 31730.456183677452 2004 32524.438516359398 2005 33152.80356510531 2006 33922.725018906254 2007 34313.3215374692 2008 33745.90605915375 2009 32754.86249773295 2010 33599.70097854757 2011 33965.444874807676 2012 34307.41964645816 2013 34567.700820868995 2014 35203.744799437394 2015 35981.099742634775 2016 36375.769339861006 2017 37101.70461235047 2018 37690.83393471512 2019 38246.740951625456 2020 36437.76933197244 2021 38538.36353310187 2022 39172.62306634395