Year current US$ 1967 238.55453148551896 1968 267.69767775736597 1969 295.87823827511704 1970 315.63101658924484 1971 341.2376200947496 1972 417.9599103055475 1973 505.83963103790103 1974 694.4588299663133 1975 911.6792035553942 1976 1128.8330122684154 1977 1173.3754291693303 1978 1257.1381522337076 1979 1471.411528814752 1980 1657.331277535469 1981 1698.4639589842664 1982 1818.9785915024231 1983 1779.3409783639925 1984 1758.7989678648444 1985 1889.661248070608 1986 1968.7091278334328 1987 2029.0296439508948 1988 1939.2443657151396 1989 1774.6012575071134 1990 2003.0971321094394 1991 1203.4196585106258 1992 1224.6915900583124 1993 1196.7093614906819 1994 1243.5447981679185 1995 1238.042003362648 1996 1351.7486832775655 1997 1436.3570503256785 1998 1467.839069510201 1999 1504.8884086105902 2000 1595.9567942664971 2001 1642.9101426890174 2002 1603.303173290431 2003 1664.1555073878817 2004 1880.2384454935348 2005 2130.254975107285 2006 2419.413361749081 2007 2827.470680359342 2008 3322.87969113321 2009 3629.6049999686657 2010 3953.206503635397 2011 4121.458588256311 2012 4616.188450827889 2013 4702.6543652623695 2014 4546.275313540315 2015 4099.251759662017 2016 3994.2933885284133 2017 3826.4574917136824 2018 3728.413978323596 2019 3589.8814191541283 2020 3199.607601870574 2021 3505.0160111206987 2022 3864.7057175013288 2023 3965.0428783261214