Year current international $ 2000 7.79953938287445 2001 9.17249478592279 2002 8.58417346327198 2003 7.39482413715473 2004 13.4044993366293 2005 11.7087162790883 2006 14.0707408828954 2007 15.0193624835049 2008 9.74841492016644 2009 12.8763714245655 2010 12.5144509639067 2011 22.4267286084016 2012 17.403561471046 2013 10.7321928350083 2014 20.3121425187007 2015 19.2874132563283 2016 17.1399644809544 2017 15.1180427594742 2018 15.598826082601 2019 17.3016208859694 2020 16.2000000444534 2021 17.2544122289578