Year US Dollars adjusted for inflation) 1991 60813.055 1992 61787.312 1993 62259.008 1994 64584.949 1995 66370.078 1996 68190.648 1997 71105.57 1998 72445.594 1999 74450.219 2000 77188.234 2001 78717.719 2002 79565.266 2003 79672.109 2004 81614.344 2005 84319.484 2006 87218.266 2007 90724.953 2008 91846.992 2009 86361.328 2010 87291.93 2011 81274.625 2012 69849.594 2013 66247.25 2014 66045.836 2015 66655.367 2016 67697.555 2017 69353.711 2018 71096.445 2019 72761.609 2020 74385.867 2021 76012.609 2022 77651.906