Year US Dollars adjusted for inflation) 1991 1065.625 1992 1096.786 1993 1132.659 1994 1196.159 1995 1249.542 1996 1308.704 1997 1368.812 1998 1391.892 1999 1460.96 2000 1512.083 2001 1560.747 2002 1615.595 2003 1674.509 2004 1738.39 2005 1814.526 2006 1914.468 2007 1999.684 2008 2093.567 2009 2187.561 2010 2311.116 2011 2440.145 2012 2578.143 2013 2727.177 2014 2875.374 2015 3024.275 2016 3170.674 2017 3328.676 2018 3492.878 2019 3663.934 2020 3842.327 2021 4024.019 2022 4208.831