Year US Dollars adjusted for inflation) 1991 8779.648 1992 9200.212 1993 9107.978 1994 9103.43 1995 9038.857 1996 9399.173 1997 9656.053 1998 9947.597 1999 10385.076 2000 10666.098 2001 10842.552 2002 10867.77 2003 11130.359 2004 11640.239 2005 11710.33 2006 11974.848 2007 12448.679 2008 12716.835 2009 13179.321 2010 13310.017 2011 13645.245 2012 13715.692 2013 13726.947 2014 13884.773 2015 13963.911 2016 14098.762 2017 14244.583 2018 14423.884 2019 14649.581 2020 14917.169 2021 15307.8 2022 15798.329