Year US Dollars adjusted for inflation) 1991 17147.504 1992 18022.484 1993 18675.865 1994 20706.023 1995 21581.713 1996 22274.396 1997 23776.908 1998 24752.746 1999 25554.754 2000 26467.629 2001 26901.334 2002 27977.221 2003 28527.723 2004 30390.521 2005 31685.965 2006 33325.75 2007 36056.941 2008 36986.316 2009 36148.469 2010 38862.805 2011 39577.809 2012 40043.137 2013 40639.047 2014 41082.648 2015 41591.676 2016 41750.754 2017 42609.125 2018 43767.559 2019 45049.926 2020 46270.07 2021 47511.445 2022 48794.578