Year US Dollars adjusted for inflation) 1991 517.102 1992 457.761 1993 477.569 1994 483.339 1995 472.47 1996 588.155 1997 633.451 1998 684.506 1999 712.013 2000 698.161 2001 769.348 2002 810.683 2003 837.123 2004 881.401 2005 936.03 2006 1007.45 2007 1058.477 2008 1108.544 2009 1156.748 2010 1213.487 2011 1282.126 2012 1358.221 2013 1425.429 2014 1527.443 2015 1578.834 2016 1587.671 2017 1599.243 2018 1629.797 2019 1678.905 2020 1745.94 2021 1812.435 2022 1936.987