Year US Dollars adjusted for inflation) 1995 4600.6696 1996 4861.85695 1997 5171.48016 1998 5457.24175 1999 5682.84546 2000 5777.21637 2001 5420.94822 2002 5670.46922 2003 6282.23185 2004 6485.02418 2005 5484.95025 2006 6736.81326 2007 7068.65177 2008 7537.63683 2009 6806.40505 2010 7100.4059 2011 7490.44521 2012 7458.86005 2013 7776.54393 2014 8124.70776 2015 8105.54025 2016 8416.94475 2017 8980.03398