Year US Dollars adjusted for inflation) 1991 55388.562 1992 55477.445 1993 57495.508 1994 57789.949 1995 57909.949 1996 58514.402 1997 59650.16 1998 60541.504 1999 62625.25 2000 62890.957 2001 62935.117 2002 63973.738 2003 65620.492 2004 65938.461 2005 66049.641 2006 66367.719 2007 66915.789 2008 65698.43 2009 66259.383 2010 66884.258 2011 67213.367 2012 68394.258 2013 68439.859 2014 68752.789 2015 69651.359 2016 70345.438 2017 71311.797 2018 71874.156 2019 72780.828 2020 73517.914 2021 74255.109 2022 74950.195