Year US Dollars adjusted for inflation) 2002 364.57057 2003 376.75871 2004 364.09544 2005 389.41636 2006 397.9859 2007 440.36816 2008 444.95014 2009 524.82353 2010 553.30029 2011 569.23339 2012 630.42741 2013 633.65841 2014 630.32001 2015 620.05652 2016 617.88997 2017 618.33279