Year current international $ 2000 23.40388259518853 2001 26.35888424066355 2002 29.5291112292992 2003 32.40051720335787 2004 34.61387159459973 2005 36.58290897365181 2006 39.665702778662656 2007 43.52707791900676 2008 46.14731747998853 2009 48.43235545455833 2010 48.95556613560549 2011 49.23694592250149 2012 51.754421063441065 2013 58.537139519800505 2014 62.54622997903003 2015 67.6048559100814 2016 71.01838824482459 2017 69.11452950994553 2018 69.15198532561969 2019 73.35531048127233 2020 73.0687176915078 2021 75.14318489775778