Year US Dollars adjusted for inflation) 1991 6999.576 1992 6914.169 1993 7041.918 1994 7136.403 1995 7324.646 1996 7600.484 1997 7469.347 1998 7255.538 1999 7264.161 2000 6755.772 2001 6510.07 2002 6445.372 2003 6348.652 2004 6401.472 2005 6252.822 2006 6418.312 2007 6570.535 2008 6817.221 2009 6443.12 2010 7280.97 2011 7421.794 2012 6824.316 2013 7751.687 2014 8205.237 2015 8240.421 2016 8390.492 2017 8533.644 2018 8658.395 2019 8845.783 2020 9018.507 2021 9197.2 2022 9377.516