Year US Dollars adjusted for inflation) 1991 8772.794 1992 8738.678 1993 8367.377 1994 7647.991 1995 7739.458 1996 7829.932 1997 7509.778 1998 7567.407 1999 7104.307 2000 7447.989 2001 7489.944 2002 7608.425 2003 7417.342 2004 7445.432 2005 7782.188 2006 7887.208 2007 7361.695 2008 7441.739 2009 7646.944 2010 7905.367 2011 7821.616 2012 7653.153 2013 7731.911 2014 8082.367 2015 8089.002 2016 7722.435 2017 7288.132 2018 7333.037 2019 7067.969 2020 6932.933 2021 6819.52 2022 6724.679