Year US Dollars adjusted for inflation) 1991 91212.445 1992 92425.195 1993 89531.344 1994 89162.203 1995 89852.602 1996 89666.25 1997 85507.133 1998 82195.016 1999 81806.133 2000 81186.875 2001 81515.398 2002 82733.867 2003 83092.711 2004 81461.305 2005 79820.422 2006 82152.711 2007 80986.922 2008 78116.57 2009 75401.969 2010 75948.562 2011 76952.07 2012 75881.945 2013 72636.852 2014 69440.07 2015 67954.148 2016 65424.824 2017 64080.125 2018 68514.031 2019 69704.453 2020 71195.82 2021 72631.25 2022 73624.508