Year constant 2021 international $ 2006 39826.98172764272 2007 40813.40372962804 2008 40264.6340895433 2009 38813.870017989764 2010 36882.21787521567 2011 32813.56875718611 2012 31614.152149623842 2013 30937.48989898919 2014 31677.08228141601 2015 32084.61734848179 2016 32068.470794701272 2017 32372.07923430514 2018 32491.23436238085 2019 33130.12669637126 2020 30333.290945586454 2021 32763.773336918857 2022 34502.31919578093