Year current US$ 1971 324.2457515483393 1972 335.1073693808771 1973 401.9965875368142 1974 483.9820415008959 1975 543.0418220137866 1976 641.0612078300946 1977 791.7704525652978 1978 856.514689442983 1979 950.8848253239972 1980 1049.026081548214 1981 1116.2954112570337 1982 1094.8339040917913 1983 1104.9054197194243 1984 1117.4426407074702 1985 1121.8792396100714 1986 803.4238962440251 1987 770.0288307359184 1988 830.9557419668607 1989 870.7729104683265 1990 765.5275081508047 1991 933.4380377793898 1992 1004.8727172997097 1993 1072.8247877534097 1994 1189.0848473899932 1995 1307.2442491591153 1996 1355.5880453130615 1997 1497.9833306915546 1998 1599.7279196298553 1999 1464.6984444555505 2000 1496.3297024043466 2001 1401.5026884854944 2002 1495.7695426156356 2003 1536.7994222085931 2004 1631.4013823550863 2005 1802.844577621064 2006 1942.6315570867828 2007 2130.6725723901886 2008 2410.707355129654 2009 2268.3893658262637 2010 2417.946360485935 2011 2722.663061775607 2012 2871.7343020367757 2013 3004.24382352275 2014 3212.699027804777 2015 3439.847119790654 2016 3560.903887189735 2017 3791.6017884099674 2018 3845.2992260700926 2019 4006.9071074862563 2020 3977.5122596977944 2021 4308.913099932366