Year US Dollars adjusted for inflation) 1994 1526.38419 1995 1563.5439 1996 1603.89699 1997 1900.59735 1998 2333.56748 1999 2683.16134 2000 2355.63328 2001 2147.99002 2002 2064.11993 2003 2205.1024 2004 2334.24099 2005 2524.26647 2006 2347.79627 2007 2249.04056 2008 2024.51554 2009 2342.2645 2010 2338.71988 2011 2441.62093 2012 2713.71569 2013 2521.18618 2014 2420.98786 2015 2641.79895 2016 2655.53946 2017 2494.05702